USB mixer controller?

I've been using Logic 9 for the past year and love it... but I don't love trying to control the knobs and sliders with a mouse. Does anyone make a controller that I could plug in via USB and assign tracks to the USB device? Basically, I would like to have a real mixing board that I can use to control the virtual mixing board- if that makes sense?

Does anyone make anything like this? I'm not even sure what to call it.

Thanks for any info!