Ck this link out

[tsubaki]

Oh dang it! I can't remember the name of the electronics that projects that info. I think it is required on all vessels for trade.
On a personal boat it would be a huge safety addition if you were over due and no one knew where you were. (yeah, I can see willy's wife now)
Seen it on a show about this marine salvage company that hated it cause their position is broadcast all over the internet and their competitors could record their movements.