Candidate for a Gigasampler Laptop. Here is a laptop setup that was used for video editing. Ok, it sounds like it needs a docking station. Still, you have a laptop to use for the less demanding applications. I am not saying this will work with Gigasampler, but if it works well for video editing it is a good candidate.

"Adobe Premiere 5.1 work fluently with DV Raptor in a docking station on a Gateway 9300XL Pentium III, 500, 160+DVD 4x and top 15", modem, 5 hours battery-power and all build in!
They even used an extra 20 GIG LaCie Firewire drive with no problems!"

Clif