There are many more WiFi options for Pocket PC than Palm, and they're also much cheaper. Unfortunately, Pocket PCs using WiFi cards don't get much more than 3 hours per charge. The Socket card and the Linksys card (covered in our WiFi review) are very frugal with power. Check out the article for pricing. The Toshiba e740 Pocket PC ( read our review) comes with WiFi built-in, but you'll not get 8 hours of use from it. If you don't mind users swapping batteries, you could always go that route (many current Pocket PC 2002 devices have user replaceable batteries).
Grayscale Palm OS devices such as the m500 get longer battery life, and the Xircom WiFi sled (also covered in our review) has a built-in battery. You should be able to ger 8 hours out of this setup. The Xircom sled is close to $300 however and it hard to find anymore. Your best bet would be to get it from Intel's website.
-------------------- Lisa Gade Editor in Chief, MobileTechReview