Erm, first computer I ever used was an IBM Sys/36 Mini, about 4 ft high, 3 ft deep, and 5 ft long, came with a 55kilo hd with 4 18inch platters and 8 read/write heads, the hd had a transparent casing so you could watch it working...

Removable media consisted of a 2400ft magtape drive, and 8in floppies, which came in 10 disk magazine loaders...

Actually, in spite of what I posted above about the Spectrum, I suppose the first computer I actually "used" was during my "A Level" maths course in 1969/70.  I never actually got to see the computer (we were assured it was "the size of a room" by our teacher), because it was in the Technical College" next door to my school, but we were given a set of parameters each week and expected to write a "program" to expedite the required solution.  And when I say "write" I mean write...in longhand, in an exercise book, with weird (almost algebraic as far as I can remember) script.

Ah, yes - lines through the zeros and all that. We actually had a mainframe at my comprehensive - it had been donated by one of the town banks to the grammar school, which was then combined with the secondary modern, so one of the classrooms in the building used for the first two years was full of something that wouldn't hold up to a palmtop these days - I've no idea what it was used for, when we had a programming class the scripts (filled in on grid-ruled paper) had to be sent to the main council education department computer for processing (or not, since the teacher forgot a vital step).

For my 11th birthday my dad bought me a Sinclair ZX81 as computers were the future - for once the old, bald guy with big ears got it right.  We soon upgraded to a spectrum and I can still remember the feeling of satisfaction gained from writing lines and lines of code to get a 4 pixel square to bob about on my TV screen.

My first "real" PC came much later and I remember being overawed by the 4GB of storage space on it - how far I've come in the intervening 10 years, I now have 1 terabyte of storage space and still feel like I need more blushes  That one is still going strong though, it lurks in the brats bedroom so he can type his homework assignments up on it.

Oh and if we are talking old games NOTHING beats the Hobbit on the Spectrum.  Damn I even have a spectrum emulator and that game on the old PC and occasionally go for a nice bit of retro gameplay.  Sad isn;t it ;o)

Commodore 16, the predesecor of the commodore 64 was my first one.  Moved unto MSX2 256Kb after that, a 8088 after that, 286 16Mhz, AMD 386 SX 25Mhz, AMD 386 DX 40MHz, 486 AMD DX5 160Mhz, AMD K6-2 550Mhz, AMD Athlon 1.66Mhz  and now AMD Athlon 2Ghz. Not sure what the next move will be and looking at Vista, the next move may not ever come.

Not sure if it counts as a computer, but I had one these as a xmas present when I was around 9/10 yrs old. My first actual computer was an A600 HD
http://www.binarydinosaurs.co.uk/scripts/picshow.php?image=g2000inner.jpg&folder=/Museum/Pong&back=/Museum/Pong/grandstand2000.php