Baluns, or line drivers, are not only easy solutions to long line-level runs, but are preferable in most cases. Balanced runs are necessary over 50' for audio (give or take), and Cat5 is easier to run & more manageable than audio or video cable, so it's win-win. Of course, it could cost more... the converters run anywhere from $80-140, and you need 2. But would you rather run a bundle of coax to a plasma, or a couple of Cat5's?

A single Cat5 can carry 4 separate signals, audio or video. S-Video counts as 2, RGBHV uses all 4. I use them whenever possible.