I found a thread on another site that had a whole list of cool wallpapers so I decided to gank the links....enjoy:

Here is the thread at Neowin that is ongoing w/ these. I just copy and pasted these and have not checked the content or quality of any of these.

http://www.deviantart.com/
http://www.digitalblasphemy.com/
http://www.shadowness.com/
http://www.razorart.com/
http://www.endeffect.com/
http://www.magnetstudio.net/downloads/downloads.html
http://www.breedart.org/
http://www.desktopimp.com/
http://www.looroll.com/
http://themexp.org/
http://www.deskmod.com/
http://www.wincustomize.org/
http://customize.org/
http://www.artofgregmartin.com
http://www.desktopgirls.com -> babes
http://misery.subnet.at/ -> abstract
http://www.rad-e8.com/ -> abstract
http://www.gamewallpapers.com/ -> games
http://www.hebus.com
http://www.endeffect.com/
http://www.shadowness.com/news.html
http://www.customize.org/
http://www.artofgregmartin.com/index2.html
http://www.breedart.org/breed.php?navi=photon%20soup
http://www.deskmod.com/?show=main
http://www.desktopimp.com/
http://www.deviantart.com/
http://www.elysium73.com/
http://www.getskinned.org/
http://www.dj-designs.com/
http://www.liquisoft.com/main.html
http://www.magnetstudio.net/downloads/downloads.html
http://peorth.host.sk/wallpapers/
http://www.razorart.com/
http://pixelcatalyst.plastiqueweb.com/main.html
http://looroll.com/thesheets/
http://www.themexp.org/
http://www.tss2000.nl/
http://www.wincustomize.com/
http://www.elw3irdo.tk/
http://www.skinz.org/
http://peorth.host.sk -> anime
http://www.animebgx.net -> anime
http://www.animewallpapers.com -> guess what? Anime
http://www.raspage.com/
http://www.deaddreamer.com/
http://www.wallpapershq.com/
http://www.macdesktops.com -> some have Mac logos but they're all cool
http://remarque.tenshigirl.com/ -> more anime
http://www.gamewallpapers.com/
http://www.wallpapers.com/
http://www.mikebonnell.com/
http://www.prevision.dk/
http://www.digitoma.com/
http://www.mandolux.com/
http://www.macdesktops.com/
http://www.digitalart.org/
http://www.gfxartist.com/
http://kickme.to/armypinup
http://www.jbedigital.com/
http://www.theimagematrix.com/
http://www.canadaka.net/
http://www.terrywitt.com/
http://www.gurugutt.com/
http://liquisoft.com/
http://soulcore.net/
http://www.shadowness.com/
http://www.thatstheplan.com/


Personal Websites:
http://www.unr3al.tk/
http://www.sybold-design.tk/
http://www.elw3irdo.tk/
http://plaza.ufl.edu/yankyzx2/