Customize.org http://customize.org/browse/latest had experienced a run of malware and spam a couple of months ago (just like dA) and to deal with it, they installed a virus scanner and blocked uploads for awhile so that the moderators could clean up the site.
The scanner is not perfect, but they are trying to find a better solution - so you still have to be careful in what you download. For some reason, it reads all windowblinds as infected, but my contact there is working to correct that.
But the best news is, that the block has been turned off and the site is open again to upload all your skins!
If you see any problems there with spam or malware, give me a shout at http://customize.org/karmat or https://www.wincustomize.com/users/2687090/karmat and I'll look into it. The site allows moderators alot more freedom to deal with issues than dA does. Now get uploading!