Textmate alt-f to move forward by one word
Solution 1:
As usual... KeyRemap4MacBook to the rescue :P Its emacs mode will give you those bindings, and you can choose a lot more bindings than that as well:
Solution 2:
FYI, it doesn't seem to be mentioned in the Mac shortcuts list, but on my Macbook Air you can press
Ctrl+option+f
and
Ctrl+option+b
to move forward and backward one word, respectively.