bill frisell uses an old digitech "echo +" to good effect, sorry for the pun, and it is basically a sampler of sorts. then there is the boomarang (I dont' think I spelled that right, sorry) and the akai headrush with something like 14 seconds of sampling. the new line6 delay pedal can record or sample up to something like 12 seconds and then phil keaggy uses something like the boomagrang to do all sorts of crazy stuff. I can't remember what it is called.
hope this helps
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