D100 Dungeon is a print-and-play solo game of dungeon crawling. It involves a 53 page book (your laser printer can easily handle it), and uses a series of tables to guide you through an adventure.
Andy Watkins has this page with an amazing list of his ratings on hundreds of historical reference books. It’s worth checking before you take the plunge on a particular volume.
GDW’s Classic RPG Traveller from the late 1970s is currently available for free at Drive Through RPG.
Like Larry Leadhead and Turnsignals on a Landraider, The Order of the Stick is a web based comic strip that pokes fun at the gaming hobby. This one, however, skewers role players instead of wargaming miniatures gamers. That’s ok. Its still really funny.
Grimdark Future is one page miniatures game set in a war-torn science fiction universe. You know the drill. The game also has eighteen army lists.