Main machine: A4000T, used for most of what I use computers for.
Development machines: A3000 desktop, another A3000 desktop
I also have an A1200 intended for use with AmigaOne when it was the symbiotic Escena design. Kept around for the occasional demo or game that doesn't like my expanded A4000T.
x86 #1: Windows98SE, used for games now and then and web pages that IBrowse chokes on. Acrobat files, as apdf isn't currently really great and runs really slow on my 060 and for the now rare need for wordprocessor or spreadsheet via OpenOffice.
X86 #2: Gentoo Linux, is close to becoming a firewall for my LAN at home.
X86 #3: Windows 2000 currently, soon to change to Gentoo Linux. Lives next to my TV intended to become a home theater PC for Tivo-like stuff, DVD player, etc. and web browsing. 2000 has proven in my case unsuitable, will change to Gentoo as soon as I get some different hardware that has Linux drivers- TV tuner, graphics output, sound card, etc.
At my "day job" I use a Sun Ultra 5 workstation with Solaris 8. I dont' even have access to a PC at work.