Folks on this thread: https://publiclab.org/n/14138 have been discussing the idea of an Arduino (Atmega 328) with no SD card for logging -- using just the built in memory. This could have several key advantages, as demonstrated by @david_uwi's work on another microprocessor in that post.
- lower cost ($2-3 by @cfastie's estimate)
- lower power usage
- less assembly needed!
Just interested in framing out that idea and inspiring other people to dig into prototyping these!