- Another vote for an underwater GPS, boat locator, and comm device
- Specially tuned handheld underwater laser that destroys only lionfish, just by pointing it at them
- Underwater DSLR-quality still and HD video camera that fits in a BC pocket, even with case
- Small inline sensor for AI computer that accurately and reliably senses tank O2%, CO, and CO2
- Tank the size of a basketball that holds 500cf of gas under incredible pressure, with compatible first stage, neutrally buoyant, and plenty of shops everywhere that could fill it
- Underwater contact lenses that make masks obsolete
- Camera-integrated database of all underwater life forms, so you can just point the camera at the critter and have it identified and tell you everything about it
- Generic heads-up display interface for all computers (works with contacts above, too)
- Online map showing all dive ops in a given area, links to reviews and SB comments on them, schedules for their boats, realtime indication of capacity, and universal one-click reservation system
- Digital cert card that holds not only a positive ID and record of certifications, but also all logged dives, DAN status, emergency contact info, etc. - standardized so any shop can interface and instantly check you in
Oh, and none of these things cost more than $250.