Alex,
I've just committed an update to Support/lib/scriptmate.rb which will let you do just this.
I couldn't find this file on my HD, and I would even less know where to find the update. Can you give a few more details? TIA.
Alain
Here is an example: (Set this as a command with "Input: None" and "Output: Show as HTML") http://pastie.textmate.org/27909