All joking apart it is perfectly feasible to paint a board(not fans as it throws them out of balance). I have done it myself just as an experiment and it worked fine. I even used silver paint for the motherboard and black for all the memory, cards, etc. Looked really cool and worked fine.
![Grin ;D](http://forum.giga-byte.co.uk/Smileys/default/grin.gif)
There is even a website dedicated to doing this.