Harddisc MP3 player

Is there anybody out there who uses a harddisc MP3 player on stage for playing pre-recorded midifiles and other music as well?
How easy are they to use if you have more than lets say 3000 songs and you want to select a new song while a song is still playing?
I use a PC, no Mac so I can't use an Ipod...
That's a pity because I like the design and it's not too big.

René

Laptops can be handy in this case. I think that you want to create a playlist for your songs? MP3 players don't have this option I think, because they just work like a CD player. Some MP3 players do have a program-option, but it's very limited and hard to edit. Connecting a laptop to your arranger is an option.

Sander

I'm sorry Sander, what I really meant is a really small Mp3-player with a size like a Minidisc- or CD-player.
These players are as far as I know brandnew and can be layed on your keyboard if you want (that's the big reason why I want such a player).
Creating playlists is very easy if you connect a player via USB to a PC.
So is there anybody who uses such a player?