Bit of an obscure one, City of Men, if anyone saw the film City of God, it is a mini series taking each of the characters in turn and giving you more of their back story.
If you liked The Wire, then look out for The Corner, which was an earlier series by same writers based in same place and many of the same characters.
+ 1 for Braquo (best thing on TV this year)
Managed to get hold of all three series of Tour of Duty as well if anyone remembers that (gave me a lifelong love of Paint it Black by Rolling Stones).
If you like military drama, then Band of Brothers/ The Pacific and Generation Kill.