Not much explanation necessary here. It's a periodic table, only with video game characters instead of those boring chemical elements.
While some are a bit of a cop-out (Batman and Iron Man aren't game characters, per se), the rest is a great mix, crossing decades, platforms and even sensibilities. Bonus points are awarded for not just visiting Day of the Tentacle's well, but returning to it.
Click the pic below for a full-size version.
IHC's Periodic Table of Video Game Characters [I Heart Chaos]