Cobaltchat.com

Garmin's new line of Panoptix sonar modules are compatible with many current and recent depth finder units, and provide a variety of functions to plot the seabed (and anything else below the boat, such as fish) in 3D. A nice alternative to the DownVu/SideVu chirp sonar that has stunning resolution but not the same 3D presentation. Check out:

http://sites.garmin.com/en-US/panoptix/