I've only got two I can really think of. This, which made me leave this warning (I couldn't resist), and this one bit of old Colbert elephant joke vandalism from way back in 2006 that I found a couple edits later by accident.

This is old but for some reason I spotted it the other day lol, in the history of the 'Jade Goody' article. I actually emailed it to someone so don't have the actual diff to hand, but there was much in a similar vein.

""Not only has Jade Goody been proven as the antichrist, but her
existance has also questioned the accuracy of Charles Darwin's Theory
of Evolution. Unlike most humans who have evolved from apes, or in
George Bush's case haven't, we can trace Jade's heredity back to that
of a pig. Darwin is said to be 'slightly aroused' at the findings.""

Aaah, here it is.

I don't know if it counts as vandalism or just good old-fashioned idiocy. Oh, and this one.

Amateur stuff when compared with some of the Jade Goody vandalism going on while she was on CBB... That one took over an hour to be spotted, as well.

That says so much about Wikipedia, I'm glad they did it.

Hey, it takes quite a while to check the veracity of each and every claim - I think 1 hour is fast work!

This was a good one as well. Adding the photo was a nice touch. And I'm not sure if this counts as a BLP vio.

This fellow performs a useful public service.

Adding a stub tag to the article on amputation is an old one, but it still makes me chuckle each time someone does it.

http://en.wikipedia.org/w/index.php?title=...&oldid=69701036

was quite good as well.

I kept a list in my userspace but later removed it.

Brian 0 lehrer, an account impersonating the real Brian Lehrer, inserted a picture of Elmo on the Brian Lehrer article. I found out about it when another user complained in an editor review, if I recall correctly.

I chanced across this edit to Photochemical reaction:

http://en.wikipedia.org/w/index.php?title=...&oldid=47938863

The vandalism stood for 23 days!

I remember looking at a World War I battle stub a year or so ago. It said something like "The Germans were able to win the battle against the British. What a poo." I imagine some bot or Vandalism Patroller got to it, but it was there for a good while. I wish I could remember what article it was. The clever subtle vandalism that isn't necessarily shocking is always the best.

Unless you are John Seigenthaler, Sr.