some models [panasonic] can't fast forward mp3s
most of them can
but it's not very good, it's only like twice as fast as actually playing it through
"real" fast forwarding only seems to exist on the ipod ... [that i've seen, i'm sure other non-cd mp3 players have good fast forwarding]
by "good fast forwarding" i mean being able to fast-forward halfway into a 2 hour set within a minute ...