Here is a bluesy/jazzy clean sound I use a lot. I generally use the neck pickup on my strat with this. Though, I have had good results with my middle pickup.
It works well for some John Mayer clean leads. If dirtied up, it could also work for some SRV, Steve Vai, and Kenny Wayne Sheppherd if you throw a wah in front.
Channel B is a little more mellow. I don't use it as much, not because I don't like it, but because I'm too lazy to step on the channel switch button.