BeagleBone Black on an around-the-world voyage…
and the Hackerbot Labs team are building an autonomous boat capable of doing sonar surveys of dive sites:
Hackerboat
An autonomous boat of unusual size
Pierce recently wrote about the latest news from the project:
Hackerboat Progress
Since the last update, we’ve gotten in the water one more time (in late July) and we’ve made some substantial design changes. First off, here’s a video of my talk at Toorcamp that Alex was kind enough to put together
Beagle Blogger 
Hey Jason, this boat is really cool! My group here at UNSW is looking at using the beaglebone for some auxiliary control of components of scientific instruments which we are building for polarimetric remote sensing. Do you have any insight as to when the beaglebone blue boards will be available for purchase?
The boards are working pretty well, but we aren’t trying to rush them to market. We are working on putting the Robotics Cape on sale so you can get a solution until the Blue is in production. You can watch the current state of the Blue design at https://github.com/jadonk/beaglebone-blue.