It seems impossible, yet it's true: in just a few short hours, Conan O'Brien's "Tonight Show" will air its 100th episode. (Yes, it's unusual for the 100th episode of a five-night-a-week strip show to air on a Monday and not a Friday, but if you'll recall...Conan missed one episode a few weeks ago.) In honor of this momentous occasion, we've collected our 20 favorite "Tonight Show" moments -- one for each week the show has aired. Up top: Conan takes the Universal Studios Tour Tram, and gives the tourists on board more than they bargained for. The other 19 clips are after the jump.

If you assumed that Tom DeLay's tragic run on "Dancing With the Stars" would discourage the former Senator from futher pursuits on reality television, you were wrong. Two broken feet can't stop the Hammer, y'all! The Texan two-stepper will re-enter the world of televised competition by hosting the "Ask the Expert" lifeline on "Who Wants to be a Millionaire." In the video, above, he compares the difficulty of being a Senator to that of being a "DWTS" contestant: "The Senate's much easier...[they're] a bunch of babies." Oh man, I hope he does "Celebrity Jeopardy" next -- imagine the possibilities! In fact, i think they should make a separate trivia show just for him and Wolf Blitzer. Now that is something I'd watch (for a quick preview, hit "continue reading").

Andy Richter serves many purposes. First and foremost, he's Conan's bro. And from what I understand about the position, it can only be held by a reliable and supportive dude. Andy can also fill in for Conan when his boss is sick or on vacation, so none of us has to go a day without laughter. And last night, we learned another one of Andy's duties -- he keeps perceived CNN know-it-all hosts like Wolf Blitzer in their places by obliterating them in Celebrity "Jeopardy!" (above). Conan would do it, but, you know, it's the bro's job to keep the world's power structure in place.

Like any good nerd, I love "Jeopardy!," and I consider the cash I'll make off my inevitable domination on the show my retirement plan. So when I learned about J! Archive, a fan-created and -curated database of every clue and answer ever used on the show, I got pretty excited. The only things missing are host Alex Trebek's way-too-authentic pronunciations of foreign words, and his other...umm, "eccentricities."

Another fun game? Compare the difficulty of the questions on "SNL" Celebrity Jeopardy! (as in the sketch above) with questions from actual games of Celebrity "Jeopardy." It's more similar than you'd think.