The most recent prank? MIT students stole a three ton (6000 pounds!) cannon from Caltech, and took it back to Cambridge. Some details are here. The MIT prankster's have a fake moving company page. There's been some media coverage about the Caltech students retrieving the cannon. The cannon was stolen in response to last year's pranks at MIT's pre-frosh weekend:
Caltech students had handed out to incoming MIT freshmen hundreds of T-shirts that said "MIT" on the front — and on the back, "... because not everyone can go to Caltech."
The Caltech squad also changed an MIT sign to read "The Other Institute of Technology," and rigged a laser to spell out "Caltech" on the Green Building.
What's funny is that the Caltech group was so enthusiastic about getting the cannon back, they had researched renting a helicopter to retrieve it, but ditched it due to issues with the Federal Aviation Administration.
The students have a freaking prank fund, which had $8,000 in it . . . which explains some of how they were able to fly students to Cambridge last year for the pre-frosh weekend, give out the shirts, etc etc.
MIT has a nice history of pranking. I really wish I could find the pictures of the shirts they gave out last year . . . I remember having seen them somewhere . . .