I'm quite surprised reading this thread and seeing two recommendations for Acer (both BMax and shoegirl). Most people see the "Acer" brand and equate low price = crap. Not true.
Last year, I started pining for a new laptop so that I could carry work back and forth from my office to home, and I also wanted something portable to carry around the building at work for configuring printers and switches and so forth when necessary. I settled on waiting until August when I could buy a laptop during the back-to-school sale period, and I wound up getting an Acer Aspire 3610 at Circuit City for $449 (regularly $749). 15.4" display/802.11g/CD-RW/DVD -- it was fairly loaded for that price point. The caveat was 512Mb RAM, but adding another 1Gb myself was only ~$60.
Now, I knowingly bought the cheapie Acer expecting it would be a one-year disposable type thing, but I now expect it'll last far longer than that. I've been very happy with it. The build quality far exceeds what I expected.
I would avoid Dells outright. We've purchased three laptops for the company (all Dells), and they've been nothing but headaches. Not a single one works 100% as it should -- each has its own personality and quirks.