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Any ideas for what my 50th should be?
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Well, there is this song by Paul Simon, named "50 ways to leave your lover" (http://www.amiright.com/cgi-bin/parody_search.cgi) that doesn´t yet have more than 4 parodies. If you wanna go with a "50" reference in the title (like I did with 25 for my 25:th) that could be a choice.

Here are some ideas for it, based on title variations only so you have to take it from there yourself:

50 ways to make a subway. (You´re pretty good with food parodies, right?).

50 Jocks to slice a subway. (With some Highschool Home Economics Class humour of the kind that will get you thrown into a locker).

50 Jocks, 2 stinkin' lockers. (Same as above).

50 ways to leave the subway. (When terrorist attack, or when you just gotta pee, or when you have just mugged someone, or... well, you get the picture).

50 dopes like Sandra Glover. (About the ongoing steroids scandal about to wipe out big parts of the American Track and Fields National team).

I´m not doing any of these myself because A) I´m already on 53 and B) I not familiar with the song (though of course that´s a minor online problem) and C) These 5 ideas all have kind of an American touch so an American will probably do them best (and I´m not telling whether or not I´m saving any other ideas for my 60:th). :-)

Good luck with your 50:th, whatever it may be.

 //  Peter