The Rabbit in its various forms is a cute little package that looks ideal for developing little serial interfaced gadgets or even ethernet interfaced gadgets. This is a classic case of the prime rule in any embedded project: no matter how cool the hardware looks, take a hard look at the development environment. In this case it is a windows hosted C-language IDE (Dynamic C from Z-world). The C language is a great choice, and there seems to be a decent set of libraries, but for someone who wants to develop under linux using his own edit, unix makefiles and such, this is somewhat of a kick in the butt, although not entirely unexpected. Perhaps Wine or VMware will come to the rescue.
The rabbit semiconductor website has lots of rabbit documents, and you can buy modules and development kits directly from them at very decent prices:
Uncle Tom's Computer Info / [email protected]