For me it was

Jupiter Ace (looked like a white zx81, 4k of RAM, 3.25M z80 Processor used FORTH as it's langauge)
zx81 (1k ram but with a 16k expansion pack that always fell off, 3.25M z80 Processor)
Amstrad CPC464 (64k RAM, z80a at 4MHz and a monitor!)
Atari STe  (512k RAM, 68000 processor at 8MHz)
PC (4M RAM, 486 sx overclocked to 40MHz)
PC (128M RAM, 486 DX4-100 overclocked to act as a 120)
PC (500M RAM, pentium 2 at 450MHz)
PC (748M RAM, athlon 1400)
PC (1G RAM, Sempron 2200 overclocked to act as a 2800)

Time to replace this one and build again q6600, 4G ram  is in the firing line :)

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Toolset: Blender, GIMP, Indigo Render, LuxRender, TopMod, Knotplot, Ivy Gen, Plant Studio.