What should I do with my poor lonely speed sensor wire, begging me to use it?

My opinion of what you should do with the wire...

1. Create a "box" with RCA inputs and outputs with an adjustment for the amount of speed attenuation based on the pulse. Don't bother interfacing the speed wire with the empeg, because if all you want is volume control, it's better to do it in an external box. For example, people who run their empeg through an external head unit could benefit from this box, too. And you wouldn't need to modify the software on the empeg to make it work. It would all be analog, in this box. For that matter, an external box could be used by people who own ordinary stereos. Such a box would be so useful, I'm surprised it doesn't already exist as an aftermarket product. If you could make it work, I'd bet you could sell a million of them.

2. Make me a relay interface that will allow me to mute the speaker on my radar detector below 30mph.

Does this pulse wire exist on all cars, and if so, where is it on my 2000 Honda Accord?