Good Laptop for Knoppix-STD

[gurr2]

I'm hoping to put Knoppix Security Tools Distribution on a Laptop.
I have a limited budget and was wondering if anyone had suggestions for what type of power i would need in terms of CPU, RAM, etc. Or any good brands or models they might suggest. I was thinking I might buy an old IBM thinkpad. I need suggestions and any would be good.

[turbine]

I've had great luck buying used desktops and laptops over at the Dell auction (www.dellauction.com). Dell auctions off machines that they've brought back from lease and have refurbished.