I have seen a lot of strange fans over the years for cooling a PC case. You can get fans that glow under UV light, fans with LED lighting made form clear plastic, and plain old black fans among others.
Sharkoon has a new fan for cooling the inside of a Pc chassis that is a 140mm unit spinning at 800rpm. The fan can move 93.85 cubic meters of air each hour and produces 12.4 decibels.
The fan uses a plain black frame but the fan itself is made from white plastic and has dimples like a golf ball. I guess this might be perfect for the golfer who also likes to roll their own PC. You can get the fan for 12.99 euros.