Today I was browsing through some of the more recent Apache projects, and came across Archiva. I decided to give it a whirl.
I didn't manage to get it to work as a windows service, and a few things (like uploading artifacts to it) were kinda slow, but overall I'd say it's pretty slick and definitely something I think I will use for awhile.
Go ahead and take a look at my setup instructions (which I honestly put together so I don't forget the steps when I go to do it at home) and give it a try. I think you'll like it.