I don't really consider this a mod, but I recently plasti dipped my rear spoiler. I like how it looks with the OEM tint at the top of the taillights and the small amount of tint that comes on the bottom rear window.
Looks nice. The spoiler on my wife's '07 was getting really bad sun fade. I took it off and painted it. (easier and cleaner than masking) But it was faded again in less than a year because I just used regular spray paint.
Thanks! Mine also was getting some sun fade and a few scratches. The plasti dip was nice because I could just rub off any overspray pretty easily with my finger or with some window cleaner.