Foobar 2000 is a "Media player with simple UI and low memory use".
It is highly editable with many "components", which act like mods. You can download it here: http://www.foobar2000.org/download

I use Foobar to replace iTunes or Windows Media Player as it uses very low memory and I can minimize it into my Notification area.

What mine currently looks like:

If you want to try to change the looks, I suggest using the "Columns UI" component as it can make it looker MUCH better than the default UI. Besides the lyrics show (another component), the rest is just doing a recolor (Which you'd likely need Columns UI for).

You can easily search Deviantart.com for more skins as you'd like. However, I did try about 5-6 of them today and it didnt look the way it did in the pictures shown and the Readme didnt really help me much at all.

If you have any questions I can help. I've been using Foobar since about February of this year and know the basics of it. I had a different look to mine this morning and when I was changing the theme around I forgot what mine looked like, so I started from scratch and adding the Lyrics sidebar (It finds lyrics for you online automatically), it looks exactly how what I wanted.