AIMP

AIMP version 3 is already released with a huge improvements, but still in Beta stage for now.
Some noticed improvements are...

+ Sound Engine: Our own output system, BASS is used now only as decoder
+ Sound Engine: Added ASIO / WASAPI / Direct Sound support
+ Sound Engine: Added 5.1 / 7.1 Channels emulation
+ Sound Engine: Added DTS / TAK formats support
+ Sound Engine: Added OGG files support with multiple track inside

+ Skins: Added full support of semitransparent textures

+ LastFM Scrobbler: Now works directly with the service
+ LastFM Scrobbler: Scrobbling track from internet radio

+ Tag Editor: ReplayGain - added ability to enter values manually
+ Tag Editor: ReplayGain - added ability to autocalculate values

Etc. http://www.aimp.ru/index.php?do=changelog&ver=300

I generally use foobar2000... but sometimes i want listen to music and watch some cool visualization... my favorites are CoR's Aorta and The Rabbit Hole... just awesome ^_^ (they are from Sonique media player btw... unfortunatelly not longer under development)

Just wanted too add to my previous comment. i now use xmplay full-time as my associated music player. the reason i changed is that aimp was a little too heavy for simple music playing but too light to replace winamp/mediamonkey etc.

Been using it for a couple of years now, couldn't be happy. Switched from Winamp, which is a huge resource hog in comparison. It has great sound quality, great features and some really nice skins. And something some people don't give much credit, is the plugin support, some Winamp plugins are compatible, and one I've been using ever since I switched to Aimp is the DSP "Enhancer" plugin. For speakers such as mine, it improves the sound quality even more, so I suggest you give it a try.

Great program. Lots of awesome skins out there, you just have to do some digging. :)
Takes up a ridiculously small amount of memory considering all of the cool things it does, and, as others have said, audio quality is excellent. I think this one is bigger outside of the US for those wondering why its gone under the radar, but once you start using it you will love it.
My main problem with it is that it is teetering on the edge of being a music library app and a simple music player, i have trouble finding a niche for it in my everyday music-playing. The visualizers are so-so, nothing to remotely compare with milkdrop or even the one in iTunes.
Online radio is a dream, even though its been done a million times before; its well presented and easy to use.
And there is NO LINUX VERSION...
I use it daily though

I love AIMP! Never heard of it until I found this page today. The options are almost all exactly what I want control over. It looks good full-sized, and in minimal-mode (which is what I use the majority of the time). The audio quality sounds excellent without even having to configure any sound settings. Having used Winamp as my main player for the past 5 years or so, I would say helped me convert to AIMP. The interface is similar and so is the configuration. In setting up AIMP the way I wanted it, I would see something and think "I wish I could change this to do that"... Then I'd check the options, and amazingly enough there was a setting for it! Great program, totally underrated, and I'm disappointed I'm only finding AIMP now.

Too bad it's no longer freeware. Everything about it is good/fine, especially the nice design, except for the equalizer. Even a slight increment in the lower frequencies tend to produce cracking sounds from your speakers, as if the diaphragm is torn/damaged. The normalizer also overdoing the volume normalization, as if somebody is turning the volume knob down too much at every chorus part of any song. Not to mention the annoying default configuration that sets the player to autoplay upon program start. Well, at least configuring it is easier than most players and sound quality is superior than Foobar2k (which has been known for its sound quality all this time) but for me to recommend this to average person is a no-no. And it is definitely not for a bass-headed person like myself who tend to tune up the bass.