Don’t change text inside the quote boxes, Clothahump.
If I was Dick Van Dyke, I’d go back in time and move that damn ottoman.
I’d go back to colonial Boston just before Paul Revere’s ride in 1775 and force him at gunpoint to go confront the British and tell them they ain’t takin away our rights.
Of course, with my luck when I got back Sarah Palin would be erroneously telling everyone about how Paul Revere “warned the Americans about the British coming”.
I’d show famous historical figures movies about their lives. Think of how, say, Alexander the Great would react to knowing how he dies.
Not original , but:
I’d visit Samuel Taylor Coleridge while he was composing a poem and pretend to be from Porlock.
What?
Dress up as Godot and go meet Vladimir and Estragon. And quickly.
That does two things. First it explains why I’ve been scratching so much and second, it makes me feel special to know that I’m one of the greatest scientific, moral, artistic, and/or political leaders in the past 2,000 years!
Or I just have jock itch.
Out of curiosity, are you going to the past or the future to meet them? 
To REALLY be a dick?
Tell Oskar Schindler to hire Poles, not Jews, for his factories. Appeal to his sense of honor that he shouldn’t employ slave labor.
Convince the Japanese army to ignore John Rabe’s “safe zone” in Nanking. Show them a book about what Rabe’s Nazis will do in Europe.
Publish Underground Railroad station locations in 1850’s newspapers.
Alert the Flight 93 hijackers to prevent passengers from using phones.
If one believes in both a historical Jesus and transubstantiation, giving Jesus a nasty strain of HIV has to rate high on the dickometer.
Go back three weeks and tell Anthony Weiner not to upload my picture to Twitter.
Find the Rosetta Stone as it was being made, and add Esperanto and Klingon translations to it.
Add modern trace elements to the paints of several classical painters, so all their major works test as forgeries.
Give a medieval alchemist a sample of gallium, tell him it’s quicksilver that’s been partially ennobled into gold, then watch him go crazy trying to duplicate it.
Tell the Confedate sympathizer mobs in Maryland about the nighttime train that Lincoln is sneaking into Washington DC on.
Leak Rudolph Hess’s peace proposal to the public, so Churchill will come under pressure to end the war with Germany by a truce.
Inside Al Capone’s Vault:
A huge banner, reading “Geraldo is a Doofus”
And behind that, the 18 and a half minutes of missing Watergate tapes and Jimmy Hoffa’s body
A bit off topic, but I read this on facebook the other day (paraphrased):
“I’m going to use age progression software on my two year and put the resulting photo on the mantel. He’ll see it all the time as he’s growing up and eventually he will realize that it’s him. Then I’ll convince him that he’s a time traveler”
I’d hang out with Sir Newton and perssuade him to take a seat under the cherry tree.
Taking photos of really obese old people and then showing them the pics when they’re still young and slim would be pretty dickish. Even worse is showing them photos like, “Here you are after you lose your leg to diabetes.”
Comeing from a diabetic - not Obese or legless :dubious: - I think that would qualify as dickish - funny but dickish
Get Jesus hooked on heroin.
Warn the Germans about D-day.