BAU

Makes me think of Gabumon. xD

BAV

the BAU is the Behavior Analysis Unit from Criminal Minds

(edit: it's a real part of the real FBI, too)

BAW

BAX

BAY
Let's get to the bay!

BAZ

can also be a name

BBA

BBB

Better Business Bureau

BBC
Whooo!

BBD

=)

BBE
Beddy Bye Eye

BBF

BBG

BBH

BBI

BBJ