Once you get Slax set up, it is a really good little system. Getting it set up is the hard part. Slax's website is full of different software applications, drivers, etc. that be added to the distro. It is hard to know what is needed, and hard not to go overboard by picking too much stuff. I became so frustrated trying to get all the stuff I needed to run my netbook with Slax, I decided to give it up and move on.
If you're looking for a small OS to run from a thumb drive, I would recommend installing TinyMe onto a 4GB USB.