Writing
History of Science
Drawing
Chinese
Billiards
Agreement. And…agreement! I loved Logic. I loved it so much, I took it twice, once as a Math class, and again from the Philosophy department!
My favorite Math class was “Number Theory.” A wonderful blend of pure abstraction and actual practical computation. Lovely stuff! My teacher used to say, “…Now, I’ll bet a cookie that the result is a prime number.” Of course, it was. On the last day of class, one of the other students brought in a big tray of home-baked cookies, and paid off all the bets. Math and cookies!
(My mother’s Marine Biology class had an octopus dissection…and octopus fry!)
Sexual Ethics was one of my favourites at McGill. We learned about the history of the vibrator and the history of the orgasm. We learned about many other things too.
Nearly all my post-calculus math courses.
Political science.
Chemistry.
Anatomy & Physiology.
Social Studies.
Weight Lifting.
Black Holes and the Universe. Had math, but wasn’t math based. I absolutely love astronomy and would take more classes, if possible. I just really, really, really hate math.
I took Latin 101 in year seven of university, to meet a second language requirement for my M.A. in the most absurd way possible, satisfying a dream of studying Latin I had since tenth grade. I’m sure Ms. Hunter would be proud should I ever run into her again.
I loved music theory, but looking back I’d have to say counterpoint was my favorite of the lot. I struggled like hell with it, the part writing and the parallels brought me to tears on at least one sleepless night. But managing to write a fugue with triply invertible counterpoint, with a stretto entry climaxing on an augmented sixth chord? Listening to my professor play it on the keyboard and say it sounded beautiful was one of the only times in my life when I actually felt like a musician instead of a dilettante. 
At Georgetown: Greek, Basque, and Old English. I still have all the coursebooks.
At St. Petersburg (Russia) State University: Russian Paleography. We had sessions in the Russian National Library where we got to estimate the age of manuscripts based on their watermarks, and studied documents written by Peter the Great and Ivan the Terrible to analyze various old forms of Russian handwriting.
ETA antonio that’s a kickass music theory story right there.
I looked down the option of taking art history I or art history II and chose II (from the Renaissance to the present) and always felt I made the right decision.
NM.
The weird ones. The way college works in Spain is very different from the US: you have to choose a carrera, a course of studies, before you even pick the college (you have to apply for course of studies + college at the same time). Choosing that carrera already sets most of your coursework; nowadays there’s some optionals but when I was in college you only chose groups called “specializations”, and only for the last two years. Everybody who went to my school to become a Chemical Engineer and took the Orgo specialization had exactly the same coursework and labs, with minor variations in course content from year to year.
While there were exceptions (mostly due to exceptional teachers), in general I liked the courses which were less evidently a part of becoming a Chemical Engineer: Electronics (analogic, to understand the machines we used), Economics (“how to speak with an accountant [and maybe extract money from him]”), Draftsmanship (that one’s cheating, since I already had 7 years of it…). And the Project, an undergrad thesis which you had to work on, write up and defend.
One of my favorites was Hebrew scriptures for a theology elective. Loved that class! The professor was the first Jewish person I ever met (seriously), a rabbi, and he also took us to his Temple and showed us everything.
I also loved all my literature courses, especially American lit. (Hi Dr. Hall!)
Business Law
Aspects of Evidence - taught by a very entertaining ex-cop and anarchist
Understanding Motion Pictures - great class for film buffs
Racquetball - I really didn’t learn anything, but every Thursday I got to play at a set time against different people.
The History of the English Language
English Words from Greek and Latin Roots
Mass Media Law (the only class I never, ever missed or slept through in 4.5 years)
Billiards
Women’s Weight Training
Philosophy. I liked it so much that I took 5 philosophy electives in my 9 semesters there, even though I wasn’t a phil major. I got a bit burned out on the topic by the end of the last class (I began to tire of the subject’s lack of practical application), but those classes taught me how to argue and how to spot fallacies in the arguments of others. Learning how to argue without flaws and without getting personal were the biggest components in my decision to stop declaring myself agnostic, and stopped me from being afraid of the “atheist” label. So, yay for logic!
Getting personal in arguments used to be a HUUUUGE problem for me… fallacies, too. Even though I’m not unintelligent, I realize I often came off that way before I learned how to argue. And I’ve come to realize that there are a *lot *of smart people out there who just have no idea how to argue (so if someone doesn’t know how to argue, I don’t automatically think they’re stupid… usually). Argument skills are a subset of communication skills, which take a lot of practice to perfect. Many walls of text have been created on this message board (and others). I’m sure some people are naturally good at it, but using fallacies to convince people to agree with you almost seems more natural than being logical (on a primal level).
Now I just need to work on eliminating excessive parentheticals, and rambling tangentially to the topic at hand. :smack:
Wilderness Leadership.
The American Legal System
And some good history classes.
Intro to Computer Languages with SICP (computer science) just amazing. opened my eyes to the possibilities of computer science as a discipline. Prof. Abelson, just wow.
Water: Planning for the Future (an interdisciplinary class, economics/political science/anthropology mostly) off campus and really unique course. Interdisciplinary courses are rare but can be excellent and this one was.
Cultural Anthropology (anthropology) bricolage and thick description, and I did some of my best writing ever in the papers for this class (it benefitted from my taking the nonfiction writing class the same semester)
Physical Anthropology (anthropology) evolution! readings from Stephen Jay Gould. so much fun.
Cryptography and Cryptanalysis (computer science) codes are very interesting. The math behind them is even more so.
Real Analysis (mathematics) real numbers are also very interesting. the professor had a riveting teaching style too. Hilbert space 
Nonfiction Writing - learning to write proper essays, autobiography, news articles, and the like. Lots of technique, only a small fraction of which stuck long term
runner ups were another math class (abstract algebra) and an art class and the compiler class
they shouldn’t have let me take algebraic topology without taking point set topology first; I did ok but I didn’t really understand it and have forgot it all because of that.
And urban anthropology was great material but the instructor was not
My freshman year was mostly a waste. Requirements and intro classes. The best was calculus and that was relearning the same thing from senior year of high school, only properly (my high school calculus teacher wasn’t bad, but the college class was amazingly well done, it made me really like math). The worst was the Humanities survey, which was also the same thing from senior year, but my high school Humanities teacher was much better.
Just finished college this spring, with a BA in history. Going to school as an adult I was better able to pick classes that followed my interests and didn’t get stuck with much in the way of dreck. I liked most everything I took. My favorite classes are easy to pick out though:
Weight Lifting: I took this four times, twice as a circuit-training class and twice as a free weight class. My first non-high school (read, “non-traumatic”) experience with PE class. I liked working out so much I took it up again outside of school (having exceeded the number of times I could take it for credit).
Astrobiology: One of two astronomy classes I took. Professor McDaid took us on an extensive tour of the solar system and showed us where we might find life some day, or evidence of where life had been. One of my Top Three Favorite Professors from my much too-long college career.
History 100: The introductory course that taught history majors to be historians. It was my first exposure to real, academic history. The leap from name-date-place-event type “history” to detailed analysis and learning to weave together so many facets of human nature and activity to tell the story of what happened in the past was the single most academically satisfying things I ever encountered.
Physical Anthropology: To fulfill my lab requirement, I observed a Golden-bellied Mangabey at the local zoo. Pretty boring, for the most part (the poor guy was socially isolated, his two fellow mangabeys having been recently taken away), until the monkey decided he’d had enough of an obnoxious woman taunting him to amuse her brats. To get rid of her, he grinned a big threat display, sat down on a branch in front of her, and started spanking the… er… you get the idea. Still one of the most fun reports I’ve ever written.
Of course I enjoyed all of my history classes, with the exception of 19th Century European History, because it was taught by a human incarnation of an Ambien tablet. I took archaeology too, and made a trip to England for a field school, though I never made enough credits for a minor. The biggest surprise was finding that I liked doing algebra (having only passed it as a kid after three attempts) and that I loved statistical analysis. If I ever go back to school, I might just look at taking more math and science.
Interesting. I am not a musician, but my favorite class during my undergrad years was on the music of Bach…we did some hard-core analyses (of a fugue, and of a concerto), but well integrated with stuff about Bach’s life and times.
Thank you, Dr. Dreyfus! (I think he’s at Stanford now – or perhaps retired. A great viola da gamba player, too.)
In my major, I loved all my computer courses.
Outside my major, my favorites were U. S. History, and Business and Professional Speech.
Course I hated the most: Economics of Money and Banking. I took my D and ran for dear life.