CanadianDiverGirl:Okay - I wouldn't suggest the carabiner as it could cause you entanglement issues (it's not called a suicide clip for nothing).
Go for a double ended bolt snap if that's where your heading.
Crystal,
Actually, any of the devices with a spring-loaded swinging gate are called "suicide clips" because of their tendency to grasp lines, nets, and other things under water, and then not want to let go.
A carabiner with a locking gate, in stainless steel, can be a useful item for certain jobs. In most cases, however, you are quite right. The bolt-snap or dog-leash style clip will work just fine!
As for other parts of this discussion, a "Scuba Duck" is a neat signaller if you need one. It has a distinctive sound.
Also, a good set of EMT shears will work well, and are acceptable in "no knife" areas.
Cheers!