I was imspired by the Trek Soho and I made my own bumber for my commuter. I used 2 layers of friction tape and used black duct tape on the ends along the top tube. If I can get my hands on a camera I'll post it but it actually looks pretty sharp and it dosent interfer with the brake cabels at all. Oh, and it looks sharp because I used black duct tape, not silver. Tell me what you think!

On my last MTB I found clear chainstay protectors. Worked great for protecting paint on top tube from sign posts and other hard points that you lock too. Can't find them at any of my LBS's any more.