I've got:
> desktop dual boot system with Windows 7 and Ubuntu 10.04 (AMD Althon 64X2, 4GB RAM, Geforce 8600GT).
> HP Proliant microserver with Atom CPU and 4GB ram running Archlinux
> A 3 year old laptop running Windows XP with a Celeron CPU and Geforce 7400 (I should install linux on this one)
> EEE Pad transformer tablet
> A very old PIII system standing lonely in the corner of my room

Two years ago I decided to make a move from windows to linux. Because I can't do that at once, I installed a dual-boot which I'm still using today. I started with Ubuntu 9.10 which is now upgraded to 10.04. I did that because I got in touch with it during a programming course at uni and I discovered that some friends of mine were quite enthousiastic about the OS. After playing it, I learned that the the commandline interface is very powerfull and allows you maximum control and ability to learn how things actually work.

I'm starting to dislike Ubuntu because it's quite bulky and still does not always have the packages I need. I discovered arch a couple of months ago and I installed it on a new home-server I bought. It's a big improvement, allthough you must take your time to install things and troubleshoot (when neccesary). I use my homeserver mainly for backups, downloads and hosting my own repositories. I'm still looking for other nice ways to put it to use, because I'm not using it to it's max potential (200MB of the 4GB of RAM is actually used lol).