If you are willing to install rockbox on an iPod then it will support gapless playback
http://www.rockbox.org/twiki/bin/view/Main/IpodFAQ#Will_Rockbox_support_gapless_pla
However read the FAQ very carefully. Here's more info from that site.
http://www.rockbox.org/twiki/bin/view/Main/IpodPort
Here's the info for the iriver. Again read the FAQs carefully
http://www.rockbox.org/twiki/bin/view/Main/IriverFAQ#Will_Rockbox_support_gapless_pla
This kinda stuff is geek territory. Otherwise thier is no other solution. No players support gapless playback.
Does any one know of a player that has gapless playback becuse I have some dj mix cds and the music rolls from track to track and it just wouldnt sound right if the songs had gaps. Thats all I needed to know.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic