My Operating System of choice is OpenBSD. I've tried various OS'ses, both work related and for personal use. Although OpenBSD has its weak points, its weaknesses hardly compare to those of other systems (in my opinion).

Currently, I have 9 working systems at home. They run the following OS'ses :
System Purpose Hardware OS
banana Workstation Intel P4@2GHz w/ 512MB RAM OpenBSD & Windows XP
nugget Laptop Intel P4@2.6GHz w/ 512MB RAM OpenBSD & Windows XP
sateh Fileserver Intel P4@2.4GHz Celeron w/ 256MB RAM OpenBSD
t-bone Test machine Intel Pentium@120MHz w/ 64MB RAM OpenBSD
baguette Test machine Intel 80486DX2@66MHz w/ 16MB RAM OpenBSD
asperge Test machine Solair UltraSPARC 1E @166MHz w/ 128MB RAM OpenBSD
alfalfa nameserver/dhcpd Digital Personal Workstation 600au w/ 512MB RAM OpenBSD
blueberry Test machine Cobalt RaQ 3 Debian Linux
potato gateway & mailserver Intel Pentium @233MHz w/ 128MB RAM Slackware

As you can see from the table above, most of my machines run OpenBSD. Some dualboot OpenBSD and Windows XP (for games or when I must use MSIE (but see this - one reason less to boot Windows)). My Cobalt RaQ3 is not supported by OpenBSD, so I chose my preferred Linux distribution, Debian, for it. Debian also runs on my XBox (not listed above). The gateway still runs Slackware, I want to move this job to alfalfa, but I first must decide what to do about my mail.

Some things I found useful for OpenBSD installs :

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