When it comes down to it, I like no die more than a d20. Probably because I've played so many games that use a d20. My favorite d20 is, ironically, the one I use the least. It's the one I got free when I went to the D&D4e launch Game Day. It's smaller than my other d20s and it's plain black numbers on a white die. But it's my favorite because it totally changed my gamer luck. For about...4+ years prior to getting that dice, I had the most horrible horrible luck finding a local tabletop game. I was only in 1 game during that time frame and it was with a group of pretentious arrogant asshats playing GURPS (and I don't like GURPS). When I went to that Game Day and got that dice, my luck changed. We turned the Game Day group into a regular D&D group for a few months before it died, but not long after I got invited to a Star Wars group that I'm still currently engaged in (I like the group, even if I don't want to play Star Wars anymore) and from that group got invited to a Shadowrun game and even before that I found my way into a Dark Heresy game. So even if I almost never actually roll that dice, it's still got fond memories.