Michael - for once I'm gonna agree with you (and Garyi etc) re Macs 
My PC has a gig of RAM, and runs XP. I'd not mind betting that the Mac's OSX "footprint" into that 256 megs is, in percentage terms, far less than XP's into my gig. The only reason I bothered upgrading my PC at all is for computer music, which I've still not started attempting to write yet, as I'm too busy playing GTA Vice City.
Now if the Mac had DECENT games for it (in addition to the, err, 3 games that came out for it since 1984) and would work with any USB device (so I don't have to pay BIIIIIG for a new printer etc) I'd leap for a Mac Mini - it looks very nice indeed 
...plus I bet OSX doesn't "forget" USB devices if you plug them in in a different order, randomly lose my desktop, change my sound settings to reverb100%, and take 5 decades to download the nth security patch
All of these have happened to me since I upgraded to XP and it's effing annoying.
Macs crash as often as PCs though - the ones in our old Design Studio were all over the place sometimes. And what on earth is an "extension" - that's the thing that puts me off a Mac - the oddness of everything 