With spring coming, I would like to build a "Save-A-Dive" kit with things that might save me from having to cancel that day's dive. Extra this, back-up that, etc. Asking around, I have gotten a wide variety of suggestions so I thought I would ask the SB community as well. From past experiences, what realistically do you recommend to have available that has come in handy, glad you had more than one of, and/or something that kept you from a canceled day of diving?