I've been talking with many people about the Archos 5 Internet Tablet with Android. There are people out there who want a really small computer that has excellent battery life. The OQO model 02 is a great machine, but it's no longer supported since OQO is no longer is business. That device does not have the best battery life, so you're also limited on that level.
The Archos 5 doesn't run Windows or Linux, but Android should be sufficient for most. I'm eager to get my hands on one so that I can test it out and see how this device would be used by health care professionals (such as gadget-loving physicians) who wish to have access to the Internet when they're out of the office.
Here are some reviews that you may wish to consider: