Finding OpenBSD was a simple mistake. Upon returning from Burning Man one year I discovered by Windows machine had died & there were no install disks to be found. Numerous *nix installations were laying around though. FreeBSD, Slackware Linux, Solaris, & OpenBSD were all attempted but alas, only OpenBSD detected all the hardware in my box right off the bat. It was the beginning of a wonderful relationship.
First off I took to setting up SSH, and allowing remote logins from outside my home's network. This was amazing to me. The ability to be able to use my computer from anywhere else fascinated me. All inside an encrypted connection no less!
SFTP was next, then setting up SMTP and Apache, slowly moving around the computer learning about included networking tools. Which leads me to my favorite part about OpenBSD... the documentation.
Type 'help' on any Mac and you'll be giving a list of possible commands to type at the terminal. Type 'help' on an OpenBSD machine and you're introduced to man pages, info pages, and Unix in general. There are a seemingly endless amount of information on commands and system tools available.
Setting up new network devices were as easy as editing text files in the /etc directory. Scripts became available as bash functions. It felt as if I wasn't going to the internet, but the internet was coming to me.
I highly recommend OpenBSD to anyone wanting to learn the ins and outs of backend solutions or just servers in general.