[TheWanderingJewels]

http://defensetech.org/2011/09/02/a-pirate-hunting-ghost/#more-14287

[farothel]

These are not supercavitating, but also stealthy:
http://en.wikipedia.org/wiki/Visby_class_corvette
http://en.wikipedia.org/wiki/Skjold_class_patrol_boat
http://en.wikipedia.org/wiki/La_Fayette_class_frigate

and theres's probably more, as other countries will be copying these.

[beowulf_of_wa]

not actually stealth but these 3 are pretty damn cool.

the spider boat (built in anacortes, north of seattle)
http://en.wikipedia.org/wiki/MAR_Proteus


the EarthRace/Ady Gil
http://en.wikipedia.org/wiki/Earthrace


and the (more names than i care to type)
http://en.wikipedia.org/wiki/MV_Gojira


of course 2 of them have been used by those whale wars folks.
the EarthRace was sunk, but i won't even get into the "they rammed us/ they got in our way" argument tween them and the japanese whalers. just don't park your speed boat in front of a damn whaler, idiots.

[Malex]

Reminds me of the boat from Thunder in Paradise.