My favorite Wikipedia articles are:
MyWikiBiz:
http://en.wikipedia.org/wiki/MyWikiBiz
(since it is about an enterprise I founded)
Jonathan Zittrain:
http://en.wikipedia.org/wiki/Jonathan_Zittrain
(because I was a guest speaker for one of his Harvard Law School classes, and he devoted a page of his book to discuss my experiences with Wikipedia)
Hogtie bondage:
http://en.wikipedia.org/wiki/Hogtie_bondage
(never fails to make me chuckle about how un-self-aware Wikipedia is)
Contribution "poem":
http://en.wikipedia.org/wiki/Special:Contributions/Wit-o-pedia
(amazing that an editor can create a string of "prose" by selectively editing articles -- have you ever seen this before?!)
Essjay controversy:
http://en.wikipedia.org/wiki/Essjay_controversy
(one of the great screw-ups of all time)
++++ ++++ ++++
Now, those are just my favorites. If you are maybe also looking for the world's most frequently accessed Wikipedia articles, there is a list for them, too:
http://en.wikipedia.org/wiki/Wikipedia:Most_popular_pages