I've been running Linux since "the early days", back in the late 92 timeframe. The first one I got running wasn't technically even a distro, being a pre-SLS release with kernel version 0.99pl2. I updated to SLS 1.01 when it came out, installed from floppies. PL6 as I recall was the first that would work with my main RLL hard drive, before that I was using my old MFM drive.

I helped with a few small kernel level changes, and did a bit of debugging through about pl13, which I ran for most of the rest of college. (Two points to the first person to guess my major in college.)
While in college I helped write the SCSI driver for the WD2000 card (based on the skeletal base SCSI driver), having acquired one of those and a massive full-height 1Gb "Eagle" SCSI drive at a tech yard sale. I also made patches to the sound sub-system to support down-mixing for non-stereo, 8-bit sound cards, because I wanted to play DOOM with sound. More recently I've tinkered with a kernel driver to use the new CM11B USB module so it looks like a serial CM11A. If you understood any of the past paragraph, you really need to get out more.
That being said... I still run a rather old distro of linux right now, Slackware 8.
(something?), with a VM setup to run a Debian based cross compiling environment for a mini-linux distro on ARM7 and ARM9 based "stamp" devices. (Confused yet?) It also runs my home web server, light control system, does DVR, and all the "heavy lifting" for network based stuff (LDAP, NetBios, file serving, etc). That said, it hasn't been physically touched or rebooted in at least 6 months.
On my laptop, which I use 95% of the time (mainly for browsing) I have XP installed. Mainly because I like being able to do some things Windows, and frankly the flash plugin works better for my online games.