I’m using a Lenovo T60 14″ with 3GB RAM and and Intel Core 2 Duo 2.3 ghz. I use XP Pro 32-bit (SP2). I have a 320GB Western Digital HDD which contains my copy of Virtual DJ and few utilities on one partition and all my music on another. It runs fast and quiet, though the HDD gets warmer than I’d like, considering it’s on a stand.
I like ThinkPads – I’ve used them for years at work and they can take the pace. As a result, my backup machine – and the one I use for downloads while I’m playing – is a T60 with a 15″ screen, 2GB RAM and a 7200rpm 60GB Hitachi HDD. I also take an external Western Digital 320GB with a mirror image of the music on the main one, which I keep up to date using Allway Sync http://www.allwaysync.com/ which is indispensible to me now. I also keep a second backup of all my music on an older Samsung 320GB HDD. Bit of a belt-and-braces job. That one never leaves my study!