[tnicola]

2 + 2 = 5; for large values of 2.

[Jach]

Or Python evil. (https://gist.github.com/1208215)

[dbaupp]

Or Haskell.

  let 2+2=5 in 2 + 2

(Significantly less mind-blowing though.)

[NHQ]

interesting and funny though for somebody who doesn't know Haskell

[FreeFull]

Or small values of 5.

[chris_wot]

So to compensate for large values of 2, provide a small value of 5?