I'm inclined to second fashizzlepop's opinion on Alienware. Dell's product quality seems to have degraded in recent years (my old Inspiron 1525 is still awesome, though), and everything that they pick up takes a bit of a nosedive. We use the KBOX appliance at work for all of our systems management and deployment. It was awesome when Kace owned it, but started to suck pretty bad after Dell acquired them and changed up the roadmap.
I'd go for a Lenovo laptop, if you can afford the higher price tag.