There is a website about 'stealthing' your bike. They mention things like spray painting it in rainbow colors and putting duct tape over the seats to make it look as unattractive as possible. I'm kinda torn, I ride an old 90's mountain bike ($45 off CL, but $400 in component and wheel upgrades). It looks pretty crappy as is, but I'm not sure I could bring myself to terms with purposely spray painting it, etc. Maybe if I hadn't built it up myself, I would not feel the same