I just got the new Nexus optical glass ports with their super optical coating that inhance clarity and contrast. A perfect match for the new digital lenses that manufactures are now producing. The glass ports are heavier and help balance out the buoyancy of the housing. The 170G port is a full radius port that can be set up to work with almost all the best lenses. The 15mm fisheye ports is for the Canon 15mm lens and it’s small size is a big help in close-up wide angle lighting. The special 14-24 port for the Nikon wide zoom lens on the D700 housing give the housing perfect balance underwater.
If you are thinking small try the Nexus strobe case for the Nikon SB400 flash unit. It is a fully TTL operative flash set. Direct sync linkage to the camera and small enough for those critical macro shots.