In fact I just finished a C Programming course at a state university. After talking with the professor I decided to continue on myself with a C++ book (to be determined), and a Linux Kernel book, [Understanding the Linux Kernel](http://shop.oreilly.com/product/9780596000028.do).
Finding a group of people of a similar skill level willing to do this type of learning would be fantastic.
It's clean, discoverable and it does interesting things. Although it might help to first go through a book like Understanding the Linux Kernel: http://oreilly.com/catalog/9780596005658/
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