Download porn.
Duh.
Lots of good suggestions in this recent Low to No Cost Hobbies thread.
So basically what you’re saying is that when you’re single, you don’t have to do anything. How boring. No cards, no tree, no cooking (I love cooking). Yawn.
OK, it’s a stupid article. But you know what else you can do? All you want, when you want?
All those things you just mentioned.
I love cooking too. And the great thing about when I experiment with my cooking; if I fail, nobody has to know.
I haven’t been single in 29 years, but reaching back into my memory, I recall playing racquetball, taking classes, writing lots of letters, knitting, sewing, doing little projects around the house, hanging out in the library, singing in a choir, flying lessons, sailing lessons… not all at once, but at various times over the course of a decade. I was a lot younger then - duh - and I was more inclined to try different things. If something happened to my husband and I found myself single now, I might look into taking a class or two, or hanging out occasionally at the local senior center, since I’m an old fart. 
But I do like some solitude.
Have you considered taking up World of Warcraft? It kills time gangland-style.
To be fair, I agree with the bit about the In-Laws.
With apologies to Alan Jay Lerner:
“They sit around and wonder,
What married folk would do.
And that’s what the single folk do.”
I come home from work, feed and water the horses, feed the dogs, medicate anyone who needs to be medicated. By that time it’s usually around 7:00. I fix and eat my dinner. Take a shower, read or watch TV, go to bed. Lather, rinse, repeat. On the weekends I walk my fenceline to make sure my hotwire is working, mow my yard, work in the barn or the pasture. I go to church and sometimes the movies. I’m busy.
StG
Take a class, join a club, join a gym, take up a new hobby, paint the kitchen, sign up with meetups dot com and make some new friends, masturbate furiously to the Cooking Channel, get a dog and train it to jump through firey hoops, volunteer, clean the house again, palnt a garden, learn to can, start up a business.
Really. Anything but “sit on the couch and watch TV and letting your brain rot.”
I go to my gym/studio so much I got hired to teach classes there. So, after work, I race home to walk the dog, race over the studio after that to teach my class. Race home again to feed and medicate the critters. Feed myself. Clean up after that. Do a couple housework chores. Run a couple errands. Find a movie or something, then watch The Daily Show and go to bed.
Haven’t been single for many years, but I got hitched quite late. I also wasn’t particularly social. This was pre-internet (at least for me) and I lived without a TV for a long time. I had several creative hobbies, though–writing, drawing, 1/12th scale miniatures, wood carving and perennial gardening among them. I always had two or three projects going at a time. And I read a LOT.
I often wish I had some of the free time I had back then.
I’m a single guy with a month off of work and spent 5 days in Colorado in the mountains then go party for a few days with good friends. Now I’m down for just sitting around my apartment doing nothing. I bought some things today to cook dinner and the Concert for Sandy is on tonight. Sounds like a nice night for a bottle of wine.
I might get motivated to get out and explore the world in a day or so but take your time and see it all isn’t the worst life for single people.
The best thing about being single is you can do anything at anytime. The worst is it’s hard to find people to do things with. Family’s, kids, recitals, birthday party’s, all seem to get worse as you get older and everyone starts having kids
Heh: “The only man who is really free is the one who can turn down an invitation to dinner without giving an excuse.” – Jules Renard
I am going to suggest taking a class at a local college (or similar) especially if it not about something you are particularly knowledgeable about. I do this at least once a year and never fail to learn something about the subject and make interesting friends of all ages. Often, the teachers, who are closer to my age, become life-long friends. Besides, it is interesting having a older person in a typical undergrad classroom.
Just finishing up "Oral Traditions’ which is really storytelling. It was great.
I also volunteer (or get paid) to teach things I do know about and find that I make interesting friends in these situations as well.
And the person who mentioned the dog had something too. My dog combines unconditional love and a conversation starter anytime we are out on the street.
Look at your milk carton; that’s now your glass.
What do I do with my “free” time? I grocery shop, pay bills, do laundry, clean the house, run errands, go to the gym, see my horse, knit, read, do assorted craft projects. I watch tv, go out with friends. My house is decorated for Christmas, I’ve sent out 70 Christmas cards. Cookies will be baked next week. I spend little time on the computer at home. The reality of being single is that while I can run around my house naked, my fun free time is limited because I have to do all the chores/not fun stuff because there is no one to share the burden. So pick one or two things you love to do, cuz that’s all you’ll have time for.
I was “single” for 4 days last weekend while Spiny Norman was away on business … and I haven’t been that busy in ages! Here’s what I did …
I went to a movie with a friend (“Lincoln” - go see it; it’s awesome).
I did a little holiday shopping.
I went to a friend’s stable with her and helped her groom and walk her horse.
I invited a friend’s kids to come for a sleepover so mom and dad could have a grown-ups night. 
I went to a friends’ house for dinner.
I had a friend come over for wine and cheese and “game night.”
I think I slept for a solid week after that - LOL
Seriously, you’ll find stuff to do. There are tons of great suggestions here already; volunteering and joining clubs are wonderful ideas.
Have fun!
Being single is every bit as much work, if not more, than being in a relationship. You know all that stuff you had other people to help you with, cooking, cleaning, shopping… you have to do it all yourself. There’s also this thing where simply spending time with someone doing something like watching TV or reading is more entertaining than doing it alone. That is, it’s time that you don’t really feel like you need to fill that, when you’re alone, you’ll start feeling like it’s wasted time.
For me, a non-insignificant reason I’m single is because I’m so busy, and I rarely go out for social reasons. Between work, gym, and interests that are important to me like music, I’m usually already busy every day, and when I was doing all these things in a relationship, I could only do so running on very little sleep. If you feel like you have a lot of spare time, pick up something that piques your interest. In my case, when i do find some spare time, I usually use it to learn something or expose myself to some new art where, when I was in a relationship, it’d pretty much just be time spent with her doing… whatever.
The no-help-with-chores thing. I can barely keep up with housework, dog training, yardwork, my day job, my nights & weekends job… Usually, either the house is covered in a thick layer of dust or the yard looks like hobos live at my house. Or the car is in dire need of a good scrub & detail. I never, ever, have the house clean, the yard weeded, trimmed & mowed, and the car shiny and vacuumed out all at the same time. I do a little bit each day to something, but I’m a team of one and there’s only so many hours in the day, and I’m the only one who cares (or not) if there are dirty dishes in the sink. So, on one hand, it’s easy to blow off and ignore stuff that needs doing because you’re only accountable to you. On the other hand, it’s really easy to blow off stuff that needs done, because you’re only accountable to you. 
Two chicks at the same time.