This technique is often used as a puzzle in ARGs[1]. It reminds me especially of I Love Bees[2]. Bits of plaintext data were added to jpgs on a supposedly-corrupted website[3], which then had to be combined in the correct order. As well as fitting the theme of the game, it's a good puzzle since the corruption gives a huge visual clue to investigate the image and it's relatively easy for anyone to load it up in notepad and find the 'hidden' data.

[1] http://en.wikipedia.org/wiki/Alternate_reality_game

[2] http://www.wonderweasels.org/apiary/guide.htm

[3] http://www.wonderweasels.org/apiary/guide1b.htm#killer