I would probably meet my grandparents when they were young, as they almost all died before I was born. The one grandmother I did meet was senile, sadly. 
I would meet my biological father. I’d give him a hug. Then a punch in the gut. Bastard.
If Jesus really existed, I’d shoot him. Same with Mohammed.
That’s all I can think of.
Most importantly, I would tell my younger self to buy socks that were all the same colour.
I suppose, as an English chap, it would be worth popping back to the time of George 3rd and allowing the colonies representation.
Tell myself to buy Microsoft shares early OR tell Apple Mac about market forces.
The five things I would do:
Stock my private zoo with Sabre Tooth tigers, Giant Sloths, Dodos and maybe a dinosaur or two. A secondary thing would be to bring back a couple of Gigantopithicus and release them in the PNW.
Find out exactly how the Pyramids and Stonehenge were built. Also find out how the Moai were moved.
Buy stocks.
Bring Abraham. Jesus and Mohammed to modern times and tell them “you created this mess, now clean it up.”
Witness the launch of humanitys’ first interstellar colonization ship.
Not being the smartest guy, I would probably do something like this:
1st use: Jump forward to lunchtime
2nd use: Come back from lunch and not feel like working, so jump forward to the end of the work day.
3rd use: Realizing that I wasted the first two uses, I would go back to the time just before lunch.
4th use: Figureing I had it “all worked out”, I would jump ahead to the weekend! :smack: Then I’d spend the weekend thinking about how I could have saved the world, attained riches beyond belief and gotten more ass than a toilet seat.
47 BC, before the first fire, convince the caretakers of the Library of Alexandria to make copies of all works in multiple locations.
On the eve of a great battle, 312 AD, I’d convince Constantine I that his dream was only a bauble from a bit of undigested potato, and any subsequent apparitions could be dismissed with a good fart, and victory would be at hand solely from his skill as a military leader.
Disrupt the Council of Nicea, 325 AD, if (2) didn’t have the desired effect.
Whisper to Mohammed in the voice of Allah—that the Virgins of Paradise are reserved for the solely for pacifists who never ever killed human or harbored designs of death for any man or woman, Muslim or Infidel.
For those of you who want to go back and beat up Hitler, I don’t think that’s really the right way to make him suffer. In his egomanical view, it will just be further proof that the German people failed him, because they weren’t racially pure enough, and now the mongrels are punishing him for his greatness.
What you need to do is show him how WRONG he is, and how a non-racist, non-nazi peaceful Germany is now once again a strong and admired country in a peaceful Europe, and how all of his ideas have been repudiated. Oh, and how Israel, a country populated entirely by those he most despised, is generally viewed as the greatest military power in the world, on a per-capita basis.
Then kill him painfully and bring him back to life 6 million times 
After reading this thread, I’d go back in time to find the point when people started thinking it was okay to be so callously disrespectful of other people’s religious faith, and do whatever I could to fix that. Maybe I’d write a book or something that just said, “You know, guys, it’s okay not to believe something and still not have to insult it,” and then leave the book somewhere conspicuous.
And of course, I’d go find myself however many years ago and say, “Go on, come out of the closet. It’s really not that big a deal.”
Ah, what the heck.
I’d go hang around the authors of books I love.
I’d alter the U.S. Constitution to give rights to those who should have had them in the first place. I’d meddle in several governments, in fact.
I’d keep my dad from ever starting smoking, drinking, and taking drugs. I’d also make him stay in high school instead of dropping out.
I’d warn my fifteen-year-old self that I’m not what she wants to look like ten years down the road, re: both the body and the hair. I figure that would scare me into sticking with what was a perfectly good fitness program, and keep me from hacking my hair off.
I’d give a few comeuppances to some jerks who deserve them. That would probably take quite some time.
But you’d be speaking German right now if you did that! (*someone *was going to do it)
Cite?
On what? The hair, the body, or the fitness program?
Yes.
I would also use my time machine to go back and devote myself to thinking up witty things, so that I could come back here and say them to people.
Next “I want to know what you like” thread, I will oblige WRT hair and body. Fitness program basically consisted of getting up off my butt and actually doing something, which I have started up again.
Better yet, take a skywriting biplane back with you, and write “[cross] ← IN THIS SIGN YOU SHALL PERISH AND BURN” in Latin in the skies above the emperor…and his entire army. (You gotta figure at least some of those guys could read. And the ones who couldn’t would still see letters being drawn in freakin’ clouds. Maybe you could draw a skull with an arrow pointing between it and the cross)
“Spike” the food and drinks, and turn the whole thing into one big frat party. Depending on what drugs you use, at the very least the bible will end up looking like it was written by Wavy Gravy.
[QUOTE=glee]
I suppose, as an English chap, it would be worth popping back to the time of George 3rd and allowing the colonies representation.
[QUOTE=Aesiron]
But you’d be speaking German right now if you did that! (*someone *was going to do it)
I doubt the United Kingdom of Great Britain, Northern Ireland and America would have any problem with another power in 1939.
The British Empire was one of the most powerful ever seen. Keeping the colonies would mean it was the most powerful ever seen. 
(and Blair would be in charge, not Bush…)
Maybe Augie could be convinced to dance and sing a Latin Translation of “Louie, Louie.” (“Iesus, Iesus” with truly naughty lyrics.). He’d probably already be in a toga.
On the morning after, everyone could scratch their heads. “What’s this three equals one gibberish? Were we really that drunk?"
It wouldn’t be sufficient, you’d have to visit Leibniz as well, as both Newton and Leibniz invented it at roughly the same time and were quarrelling over who invented it first back in the days.
Since there seems to be a lot of people up in a tizzy about not only what Jesus said, but how he said it and what he meant, I would go back to that time and document everything he did myself so that there isn’t any room for historical inaccuracy to pop up.
I’d go back and make myself do some things I am kicking myself now for not doing.
Go back and see some of the greats in magic perform their act. I often wish I could have seen Harry Blackstone, Thurston, Houdin, Kellar, and Houdini back in their heyday.
Go forward about 500 years or so and see what society will be like… you know… make sure we haven’t killed ourselves yet and stuff… just so I can come back and continue my existance with a little more peace of mind.
Hm. So what you’re saying is that regardless of whether or not we won our independence, having us as a colony or ally (we’d probably be a Commonwealth nation by that point) is necessary to’ve kicked Hitler’s ass?
I can agree with that. 