I see a lot of good general advice, but not too many specific examples. Here's a very specific one... If you want to do C and get an introduction to a bit of a

I see a lot of good general advice, but not too many specific examples. Here's a very specific one... If you want to do C and get an introduction to a bit of arm assembly, you may want to contribute a new model build to CHDK, the Canon Hack Developer Kit. There are always new models out that need support, like the Canon PowerShot Elph(US)/Ixus(EU) 160. See http://chdk.wikia.com/wiki/Category:Porting http://chdk.wikia.com/wiki/Category:Porting for some hints to get started. The CHDK core devs are really friendly and often available on IRC and forums. That helps a lot.