So, I was discussing Mystery Science Theater 3000 on IRC, when I decided to look for one of the fan-made versions of popular movies. I saw one of Star Trek V at a con years and years ago...

And I found that Mike Nelson, formerly of MST3K, is now making Rifftrax, in much the same style.

http://www.rifftrax.com/

For popular movies, you can download the mp3 file and play it synced with your DVD (manually or using the Windows-only Rifftrax Player). For public domain movies, you can download or stream them pre-synced. You can even upload your own tracks to sell.

I'm looking forward to watching new-and-improved Twilight. I thought it was funny the first time I watched it...