Does someone now the benchmarks of the apple poverbook 1,5ghz versus the pentium M laptops?
IBM Thinkpad T42p looks interesting! Its more expensive then the macs, though
but ok, I asked for it 
An ibook is out of the question! try to run Live 4 with two tracks, one with the Kompakt sampler, and one with korg legacy MS20... its not possible!
Im not even shure if the top powerbook from apple can handle live, with its 1,5 ghz G4..