The first ones I saw were on E46's and they turned out great. There are plenty of examples floating around. Since it's been kind of dead around here lately, figured it would be fun to have a discussion. Here's an example:
http://www.e90post.com/forums/showthread.php?t=777877
I'm a DIY kind of guy, plus I plan to keep my E92 M3 for a long long time (if not forever). I've toyed with the idea of dying my interior another color just to change things up. Our cars are so much easier to do than E46 M3's (assuming you have non extended leather) because we'd only have to do the seats and door panels. The E46 guys have to either find a new dash, or dye the bottom portion.
My car is Sparkling Graphite on Bamboo Beige. I've absolutely fallen in love with this combo (I'm the 2nd owner), but thought these would look awesome as well:
Cinnamon (from E46 M3, not the newer BMW's)
Sakhir Orange
Imola Red
What color would you chose to dye your interior?
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Current:
16 F82 M4 GTS, Black Sapphire/Black, DCT
08 E92 M3, Sparkling Graphite/Bamboo Beige, 6MT
07 E85 Z4M Roadster, Alpine White/Red, 6MT
99 E36 M3, Techno Violet/Dove Grey, 6MT