Wow, thanks for putting this together! I always find it fascinating to see how other icon makers go about making their own icons. I have no idea if Gimp has a pen tool...I'll have to check that out. Whenever I want to 'cut out' part of an image I just use the eraser with a fuzzy round brush to remove the part I don't want. I've tried using the scissors tool but I find that to be annoying.