Hasbro has launched a line of action figures — Xevoz — that can be customized with interchangeable parts and then sent into battle against each other using a pretty innovative looking (if simplistic) combat system.
I’ve seen a couple of customizable action figures games (mostly collectible ones aimed at the RPG/CCG crowd) — none of which, to my knowledge, have been particuarly successful. This looks like something that might actually succeed depending on the pricing for the action figures.