Well, I don't know about S-video. I have a device that converts VGA to RCA, and it serves me well.

The thing with these devices, as far as I've found, is that one with a quality output costs a heck of alot of money. Therefore I think if it has S-video, it'll be a device designed for very high quality output, thus costing you a pretty penny.

This is what I am using.

I've used it at parties to output Geiss onto the 45" TV in the living room. Very trippy stuff. You'll find that pretty much anywhere, it costs ~$100.

DiGNAN
Ob-La-Di, Ob-La-Da, etc.