Just came across a very nice list of Game Mechanics on the Board Game Designers Forum. What's a game mechanic, you may well ask? It's an element of game structure that describes, for example, how cards are drawn, or how the abilities of pieces differ from each other.
The referenced page is part of a wiki, and so not all pages are complete. It's a great resource, though, when you're at the early creative phase of developing a board game. It provides a pool of ideas that probably go beyond what's already in your head.