RP-350:  The large pedal on the left is a multi-effects processor.  I don't use a ton of effects but this does help a great deal.  

Mutron III+:  The pedal at the top of the picture is a Mu-Tron.  This is the effect that Garcia used on songs like Estimated Prophet.  The III+ is apparently a remake and is not the same quality as the original but it works in a pinch.

Jam-Man:  This is a looper.  I can't say enough about this thing.  You can record rhythm tracks on the fly or use pre-record loops.  I added a 2 gig Flash memory card so you can store something like 4 hours worth of loops 

Tuner:  Enough said.

3-Button Footswitch:  This just allows me to toggle between loops on the Jam-Man.  This allows you to record a loop for the verse and perhaps the chorus of a song and then switch between them while playing.