I earned my stripes programming 68000 assembler on Fat Macs. (Okay, before that I hacked around with BASIC on an Atari 400). My 512K Mac lasted me 7 years, maxed out at a meager 4 Mb RAM as a Plus. Since then I've had a PowerBook 540 (5 years), a PowerMac 6500 (3 years), a PowerBook G3 (3 years), and a PowerBook G4 (4 years; my current device).