Protools And Powerbook, running protols oon a powerbook Options

[rexxx3]

i've been running protools LE on a G4 and am about to purchase a powerbook,
is there any alternative to either the M-box(only 2 inputs)or protools LE 2(not very portable,expensive)
It's seems strange that there is no way of recording multiple tracks on a powerbook other than buying a very expensive pci chassis for your protools LE or recording into E.G logic through a motu and then importing it.