In the new Powerboat magazine, they show a new remote called the iDrive, that mounts into the hub of the steering wheel on your boat. Looks really good, and clean.
I have used them with an Alpine Deck and they are great. You plug a "dongle" (not my word) to the back of the HU and you can use a remote (i-rock or i-drive) to control the radio. You can use it with existing wired remotes. I have used the i-rock upto 300 ft away through walls. Plus it is water proof and floats. I have 2 for my new boat (on on the beach at all times and one in the boat on a lanyard for when I wakeboard).
www.h2owaves.com