best app to stream movies over the web

best app to stream movies over the web

I have an old box that I'd like to use as a private sever to stream movies off of. My upload speed is about 0.5/Mb/s, so I need something that compresses well. I'd like to be able to access these movies from anywhere, through the web, through some interface (maybe the divx web player? flash player? some other protocol?) Can anyone recommend anything good? (Using Windows XP)