Portable, High Performance, Computing Options?

Mostly a lurker asks: "I am a consultant with a need for a high performance machine (fast I/O and minimum 1GB RAM, perhaps more) with which I sometimes travel. I am willing to accept anything up to a 20lb traveling weight, but it must be compact enough to take by air. I would obviously welcome something that does not break the bank. Right now, the best I can come up with is something built around the Shuttle SB51G XPC with a separate LCD monitor and keyboard. It is really frustrating at the apparent lack of good alternatives. If I could wait six months then, the best desknotes would probably fit the bill (with the new IBM 7200 RPM drives). Today's desknotes fall short on I/O performance, and I would not be able to push RAM past 1GB. The lunchbox computers that qualify for air travel are mostly expensive rubbish, unless one's main concern is ruggedization. All-in-one computers like the IBM NetVista, Gateway Profile and ECS Aio's also seem to fall short. So, am I totally missing another great option? Have I mis-evaluated one of the options above? If I go the Shuttle XPC route, is there a really good light (and, equally important, compact) LCD monitor out there that someone wants to recommend [15" minimum, 17" would be nice, 30ms refresh or better, XGA acceptable, SXGA nice]? Thanks."