howto hack the law - https://www.youtube.com/watch?v=BWdkSGuGOfQ
enemies of the state - https://www.youtube.com/watch?v=oH2tJcU9lqU
- Writing a Thumbdrive from Scratch - http://media.ccc.de/browse/congress/2012/29c3-5327-en-writin...
On the social/political side, I loved http://media.ccc.de/browse/congress/2012/29c3-5305-en-long_l... It's more about conveying a perspective than information, though.
http://media.ccc.de/browse/congress/2012/29c3-5275-en-factha...
http://media.ccc.de/browse/congress/2012/29c3-5393-en-milkin...
http://media.ccc.de/browse/congress/2012/29c3-5319-en-certif...
http://media.ccc.de/browse/congress/2012/29c3-5152-en-hashfl...
http://media.ccc.de/browse/congress/2012/29c3-5219-en-how_i_...
http://media.ccc.de/browse/congress/2012/29c3-5256-en-the_fu...
http://media.ccc.de/browse/congress/2012/29c3-5206-en-the_et...
Just a lot of fun ways to abuse x86 page tables.
- Low cost microprobing
This was probably the most practical explanation of what's involved in setting up a microprobe workstation that I've seen. Not a ton of depth, but interesting.
- Writing a Thumbdrive from Scratch
Starts with a good premise and goes into sufficient detail to be interesting.
- FactHacks
Best vaguely mathy talk. For some reason, I'm always surprised when I see video of djb -- he is a very good lecturer.
I've heard Everycook was good, too. Still need to watch it.
For some mathematics/security: Facthacks
Topmost on my to-watch list right now: Hacking Cisco phones.