I use one preset per song, though many of them use copy-pasted amps.
From what I know, Beck uses a guitar, a cable and an amp... Anything else is manipulation of the guitar.A couple of artists that always impress me with their plethora of different sounds and effects (even during one song) are George Lynch and Jeff Beck. Of course, I realize a lot of this has to do with their technique and how they use their guitars (trem, volume/tone knob, etc). But there's no denying having a certain palette of "effects" is a major part of this equation - especially with George.
From what I know, Beck uses a guitar, a cable and an amp... Anything else is manipulation of the guitar.