There is a new product available on US market.
PLB - personal lacator beacon
http://www.acrelectronics.com/PLBorig/gypsi.html
which is a small EPIRB, satellite and GPS enable. It's fully functional EPIRB, but it's registered wich CG to person, not a boat. I wrote in application that I sail small open boats solo, so CG w'd know what to expect.

I believe, for $650, it's a good life insurance:)

Regarding subject - I'd check a boat in trouble in front of me, but, probably, not a boat well behind...