
The only UW housing I know of is Ikelite's #6071. At nearly 1000€, not really cheap for a polycarbonate housing, even though rated to -60m. Nor what I'd call a travel light solution at around 4kg including camcorder, but without any of the inevitable accessories.
→ Canon HV20 review by Camcorderinfo
→ Canon HV20 review by SimplyDV (5/5)
→ Canon HV20 review by TrustedReviews (Recommended: 9/10)
→ Canon HV20 test shots by Videoaktiv (71/100)
→ Canon HV20 report by Wofgang Winne (in German)
UPDATE: Canon has announced its next HDV model, the HV30.