Benny, I think that there is something out there for that specific reason. It is an adhesive pad that is placed where your palms rest. It is a slightly darker grey than the titanium and actually looks quite nice.

As far as the painting is concerned, I am pretty sure that doesn't void your warranty. Also, I can't say that I have seen a black powerbook, but I would love to. If you proceed with the mod be sure to take plenty of pics and document your work so that others can see.
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"Fix it 'til it Breaks."

Jacob - EiC & Director of Technology
Mac Pro Quad 2.66 - 4GB RAM
160 GB SATA RAID 1 - 650 GB Storage
Quad 19" Widescreen LCDs
Accessorized to the Hilt