I'm a Mac guy, plus I use Windows of different varieties. I run two Windows 2003 servers, my own Exchange server, have several Macs and have a few other flavors of OS'es lying around somewhere like Vista (totally useless). I tinker and love playing around with operating systems rather than playing games (yeah I know it's a sickness).
I never could get into Linux. I've run it a few times (Red Hat and SuSE, and Slackware back in ancient times) but didn't care for it much. The most I tinker with Linux is when I'm trying to hack my TiVos.
As for web browsers, I use mostly Firefox on both Windows and Macs, though I do use Safari and OmniWeb on occasions on the Mac and IE on the PC when I absolutely have to.
