The Art and Craft of RPGs
RPGs have come a long way from the random dungeons of the 1970s and early '80s (although I still have a soft spot for random dungeons and Little Old Men yelling "Secret Passage!"). There are websites devoted to classifying games, to studying the theory behind them and even academic studies of the psychology of gamers. And roleplaying games have been used as educational and therapeutic tools (though the latter use is likely, I think, to derive more from the roleplaying than the game part).
Here, though, we're interested in much more prosaic skills - the simple nuts and bolts of gaming, the little tricks which will make it easier to prepare and run games. I love reading other people's tricks and techniques, because whether I agree with them or not, it gets me thinking about my approach to gaming and how I can improve it.
In addition to my own material, I'm also hosting Dan Cope's excellent Uncle Figgy's guides, since Dan's own website has vanished into the ether, and a few pieces I've had since the days of Usenet.
Gamesmastering: The Art of the Illusionist - a work in progress.