I would like to do something like this Textmate tip, so that trailing whitespace are always highlighted in some way when I code something in Python - it makes it easier to corre
I don't know how to highlight the trailing space but you can remove it by going to
Bundles -> Text -> Converting/Stripping -> Remove trailing spaces in document
Also, because textmate has emacs bindings, you may be able to do it the same way you would do it in emacs.