So, I found this manufacturer of ultra-lightweight carbon fiber and magnesium wheels.

http://www.dymag.com/index2_e.html

If I decide to keep my Crossfire or get anther one, I might just look into this. Right now roughly $2,000 per wheel is not in my budget at all, but I would like to inform everyone who would want to reduce unsprung weight of our cars to look into them. People mention the Crossfire's drivetrain sucks an unusual amount of power going to the ground, so maybe some lightweight wheels will help. The manufacturer told me they can get group-buy rates too if many are interested, don't know how many yet though.