This deserves a separate post. Here's some C/C++ embedded tutorials from Dan Saks which i really enjoy reading and always get back to them when I have a spare time. I include a link for all articles which he has published on the embedded.com.
Embedded.com - Programming Pointers - Dan Saks
Beginner's corner (collection of articles) short list but worth reading:
Embedded.com - Beginner's Corner