Another very unique accent is Cajun...from Louisiana. Lots of French influence in it.
Justin Wilson had a very famous Cajun cooking show:
http://www.youtube.com/watch?v=eK4umRMJlrs&feature=related
Also heard pretty thick with some on http://www.youtube.com/watch?v=5KzeYrjfN9s...from the History Channel.
I find it to be a fascinating dialect.
I love Cajun. I think it has something to do with my growing up watching the X-Men cartoon, and Gambit being one of my favourite characters.
I find real true Cajuns very difficult to understand. I had a great friend who I use to talk to quite often who was from the swamps and ooo wee! It sounded like he was talking a different language all together sometimes. lol He sounded like some of the guys on that Swamp People show. Really smart guy though people seemed to dismiss him because of his accent.
And omg, I just realized who you linked to! I use to LOVE watching Justin Wilson! lol Which I guess was obvious with my 'ooo wee' comment. Thanks for posting that link.. total nostalgia.

lol And I use to say "you all" until I was about 10 and made friends with a girl from South Carolina. Now I say "ya'll" and if I try to say "you all" it just sounds so odd. (And that was like 20+ years ago so, I'm thinking it's going to stick.)