Would you pay for a karyoke cable?

So, it turns out that it's really easy to make a cable that removes vocals. I saw a Forum on Superuser or Stack Overflow that told me how it works. Basically, audio engineers put their vocals in the center. When you take them out, you tell Audacity or whatever to take the equally balanced vocals and remove them.

I have an audio cable that does the same thing. Apparently, when the ground-pin thing isn't working (sorry I'm not too technical in hardware), the vocals get removed. This works about 50% of the time, but I'm wondering if I can sell these things and get a karaoke cable. They're cheap to produce, and I could easily start a Kickstarter campaign to produce these. It's a lot of work, but it's easy to do. I could probably even make them by myself. Would you buy one? Maybe I'll put them into production.