On #haskell we recently had a discussion about the following:

   import System.Random

   list <- replicateM 1000000 randomIO :: IO [Int]

I would think that this gives us a list of a million random Ints. In
fact, this is what happens in ghci. But with ghc we get:

   Stack space overflow: current size 8388608 bytes.
   Use `+RTS -Ksize -RTS' to increase it.