>What music formats can be played on an MP3 player, and more specifically, an iPod?
>
>Can WinMedPlayer WMA files be played?

Most of the players should accept most of the formats :). The slicing of the market into proprietary formats and DRM encodings makes it as clear as a cell phone contract.

I know the Sansa we bought plays mp3, wma, and probably ogg, I wouldn't know. I'm not using it. I only filled it with about 2.5G of mp3 music for the last trip, and had it plugged into the car stereo. The daughter was the DJ, she would know.

>Strange how a 6-odd mbyte track in .wma takes up just 1K as a .cda on the CD

.cda is anything but short - it's an uncompressed wav file, and it takes a whole CD to store 74 minutes of that. What you see as 1k file is probably a separate header file.

>Is a .cda track emailable?

If anyone has such a huge mailbox and is willing to accept 80M per song :).