They just released a version of the eReader software (formerly Palm eReader, then just eReader, now the Barnes and Noble eReader) for the Android platform.
It’s a little bit buggy: you need to wait for an entire book’s table of contents to load before reading/scrolling, else the book will get stuck partway through. Other than that, it works great on my G1. Nice to see a commercial ereader on a Linux platform. (Yes, the books still have DRM, but the format’s got some longevity behind it, and is supported on enough devices that I’m not worried about getting locked into one platform).