I have a little IBM ThinkPad that my husband picked up cheap from work (they're always dumping inventory). It does everything I need to do, which really isn't much. Its a little big and bulky, but so far I'm happy with battery life and speed.
Again, I don't do any real graphics or anything. I just need to internet access, MS Office stuff like Word and Excel, really just very basic.
I did kind of get excited the other day when I was picking up my new cell phone from Verizon. The guy showed me (thankfully very low pressure) the new little Netbooks and I was impressed. For $200, I could have all of my necessary features, a full keyboard, and I could have internet access anywhere I have a Verizon signal. No more having to find a coffee shop with wireless! Of course you will have the extra fees (business write off's) for the service, but seriouly, this thing would fit in my regular purse. Its going to be on my wish list for this next year.....first goals are to be making enough at my business to pay for the kids' extra-curricular activities (of which there are many), and a twice monthly manicure (ahhhh the luxury), then I'll start looking at new toys!