Dirty Cops-
The Shield-Excellent series on FX. Shows you what to do :-)
Gang Related- Starring Jim Belushi and Tupac. Not worth the $15 bucks I spent on the DVD, but worth a rent. Shows you what not to do :-)
Solo's
Collateral
Man on Fire
Punisher
The Bourne Identity/Supremacy.
Just some movies I've watched within the last week that gave me some inspiration.