Here is my config, please let me know what you think:

CarNetix P1900 + P5V

19V Primary (140W available) > Motherboard
12V Secondary (shares 140W with Primary) > Screen
5V Tirtiary (15W available) > USB Hub

The USB Hub uses all 15W I believe.

However, I still need another 5V/10W for my external USB DVD drive.

Where/How should I power this thing?

I was thinking of going Firewire. I believe a bus-powered external Firewire enclosure can draw up to 10W from the motherboard and not require a seperate power supply... like this one.

Any suggestions?