I don't know if they are as good anymore, but the model I had 3 years ago was a great deal. I was able to tinker with it a lot as well and I like the self recovery that is installed into the harddrive itself. I'm when they were breaking into the market, they built much better computers for the price. Not sure what they are offering now, but they got some good deals on low-end laptops.
It's called skillz and the fact that I got them to build my own hardware. There is gratification from building something tangible, I'm guessing you would never know what it feels like. As for the money I saved, I simply re-routed into gold & silver, it's essentially the only thing I trade now. Oh, and a custom made laptop that is worth more than your whole trading setup.
I just received ( and set-up ) a new Inspiron 530s ( the slimline model ) for a family member who purchased it out of the Dell January catalog for only $349.00 Intel Dual-core E5200, 2.5Ghz with 2mb of L2 cache, 800 FSB, and 3 Gigs of DDR-2 800MHz RAM, DVD read/write, media card reader, Windows Vista Home Premium, 320 GB HD, speakers, keyboard, mouse, added an ATI Radeon HD3450 with 256 mb for DVI and HDMI. 1-year warranty. Very slim design. Pretty sweet!
For others who might be thinking of getting one of these SFF rigs... there may not be PSUs available nearby should yours need to be replaced. The SSF ones are much smaller than standard ones.