I purchased the Samsung YP-T10JQW 2gb MP3 player 2 years ago. I commute by train to and from work, one hour each way, therefore a good MP3 player is an essential. Previously I had always bought Phillips, but my last 2 Phillips MP3 players inconveniently seized up. I purchased the Samsung one from Currys for £69.99. I can honestly say it is the best one I have tried. The battery life lasts for ages. I can listen to it for 2 hours a day and it only needs recharged about once a month.
It is a reasonable size, not too small, but it is very slimline so fits in a pocket easily. The screen is touchscreen, and is also an excellent size. it has a lock function so it doesn't skip tracks while in your pocket.
One of the best functions has to be the ease of which you load or delete tracks. Simply connect it to your pc and drag and drop to load tracks, or select and delete to delete tracks.
You can load and view pictures and videos as well as music, and the sound quality is superb. All in all, I would highly recommend this as an MP3 player, and if my current one ever broke down I'd make a beeline to buy the same kind again.