I think it would make a fun puzzle if you took about 50 "before and after" photos (commonly found in magazine ads for diets, surgery techniques, hair restoration, bodybuilding, etc.), split the befores from the afters, and then put them on two different pages of a magazine and let the user try to figure out which goes with which.
Sound easy? I don't think it will be. Those dieting people usually get a whole new hairstyle to go with their new thinness, often blossom into color from black-and-white, and usually grow a few inches taller as well. You will have to work back and forth and use elimination to identify the correct match.
It will be an entertaining, popcorn type of puzzle you can do on the bus. Feel free to add some funny ones too. I once saw an ad for something about how women can get their husbands to be more considerate of them, and the before picture showed a toilet seat up and the after picture showed a toilet seat down.-- phundug, Jan 31 2006 [flickr] haircut http://www.flickr.c...ncarleton/86621287/ [jutta, Feb 01 2006] [flickr] nothing discernible http://www.flickr.c...hotos/amm/72584496/ [jutta, Feb 01 2006] [flickr] 8 weeks of dieting http://www.flickr.c...dythegeek/70736309/ [jutta, Feb 01 2006] I was hoping this would be a 'before' and 'after' jigsaw puzzle, with before on one side and after on the verso.-- neilp, Jan 31 2006 [Hm, harder to find examples for this on flickr than I expected.]
Some of the people could be transgender.
In another type of puzzle, players could guess what the intermediate event is.-- jutta, Feb 01 2006 I like! The intermediate event one would be more fun than matching folks, I think, because of the possibility of amusing hypotheses.-- bungston, Feb 01 2006 random, halfbakery