I like Windows Media Player. And my preferred portable mp3 player is the Creative Zen.

Quicktime is OK and so is WMP...I prefer Quicktime though....WMP can't play a lot of formats..

Oh no. First Real Player and then Quicktime. Ouch.

OK, my list is WinAmp (sometimes FooBar), VLC, XBMC, Sandisk Sansa. I recently won a no-name mp3 player with video and crap, but it was way too clumsy to use. Sold it at the flea market for $15.

I like the Zens for mp3 players...the new Zunes are pretty nice though...perhaps when the next generation comes out I'll buy a current generation Zune hehe.

And I do like VLC, I just wish they'd make a better interface and playlist organization. They could be the be-all-end-all of media players if they looked better...even the skins available can only do so much.

Jet Audio, for video

It's the best, it plays almost every video format, covert everything to avc/mpeg4 in any configuration with is excelent for my ipod, ps3,psp it blends the subtitle with th video, what for me (see everything subtitled) is terrific, and it's very easy to use :D, it plays dvd to.

to manage music, itunes, it's ok

foobar2000 for music - excellent music player, and if any of you have Linux, Amarok is THE best music player software full stop. That much is FACTAROONY!

For video and the like, I install K-Lite Mega Codec Pack with Real and Quicktime Alternatives, mix them with Media Player Classic and you've got pretty much EVERY aspect of video and audio covered that you could ever possibly need.

I have a Creative Zen Touch 20GB MP3 player which I've had for over two years now, and the thing is just brilliant! Excellent battery life, pisses over iPods (most things do!) and it's just great to use. Will definitely be going back to Creative when this one kicks the bucket, but theres plenty of life in it yet, it's how well built they are, again - iPods can't touch em! 

I love Winamp for audio, I just think it's got the coolest interface :P

For video I use VLC, because it just plays everything xD and that's cool.

My personal favorite mp3 device is sadly my PSP, I keep about 600 songs on it, videos, comic books and games :P

 Really now? Is that free-ware? Or what's the deal? That sounds pretty awesome :D

unfortunnely the free version only allows 30 sec video converting, I don't know the price of the full version, but I downloaded the complete version at mininova.org(Here http://www.mininova.org/tor/1058245) =/.

It also converts audio files :D, almost any format, any bitrate

this made my life soo much easier

VLC all the way. Supports multiple OSes, and many if not all the codecs. A lot better than some of the other junk like WMP and Mplayer. :)