A fad on Project Dark Star that started with Rick's Let's Play: King's Bounty and exploded from there. A Let's Play is a bunch of posts with snapshots of a game, with commentary. Let's Plays are literally just playthroughs of games for fun, and can be done in text (for old IF games), screenshot (most games) or video (also most games). Generally, one can craft epic tales of hilarity and wonder with the games, just to make it that much more enjoyable for the reader. Snarky commentary is generally needed for video LPs.