The iRiver ifp-795 arrived. It has everything you would expect from an mp3 player and some more (including options like timed radio recordings). By default, it only supports its own protocol for filetransfer (but there are linux drivers for this ifp protocol). I installed the UMS (USB mass storage) version of the latest firmware. I can now mount it using the usb-storage driver, so I can rsync stuff to it. The user-interface takes a bit getting used to, but the basic functions (play music!) are simple. It can also record from line-in or built-in microphone, I will experiment with that. I filled it with nice podcasts, and I listen to them.