Well, you mention the blues scale which is pretty common.
Akin to that one, adding chromatic notes from the b7, 7, R adds some funk as well as the #9 chord, which the guitar plays in just about every James Brown song ever.
Just like the A blues scale has three notes in a row - D, Eb, E, add a note between G and A, so you get -
A B C D Eb E G Gb A
I left out the F#, but you can add that if you want.
Good ol' pentatonic sure rears its head in a lot of funk - A C D E G
The #9 means you use both C natural AND C# if you are playing a chord (again in A), on bass playing off that half-step gives some interesting sounds.
But as people have pointed out already, it is 2011, you can play anything over anything and make it work if you really want.