Stephen Diehl's protolude library is excellent. I highly recommend it as a default prelude for Haskell.
It's so good and so close to what I want that whenever I do come across something missing it's as obvious as a glitch in good music.
Here's what I'd like:
(<<$>>) :: (Functor f, Functor g) => (a -> b) -> f (g a) -> f (g b)