shameless plug: my ncurses thin SPV bitcoin client for linux/mac:

https://github.com/bit-c/bitc

  * 100% C code,
  * support for linux and mac platforms,
  * console based: uses ncurses,
  * home grown async network i/o stack,
  * home grown poll loop,
  * home grown bitcoin engine,
  * supports encrypted wallet,
  * supports Tor/Socks5 proxy,
  * multi-threaded,
  * valgrind clean.

You'll need basic dev skills to install it: check-out the code, install dependencies then build. It's all in the README file. I'm interested in all kinds of feedback you may have: feature requests, bugs, etc. Thanks!