Scuba diving is the only way left to find hidden treasure, befriend a nautical skeleton, or strap a huge tank to yourself. Explore the possibilities with today's Groupon: for $39, you get an Introduction to Scuba Diving program at Ascuba Venture (a $79.95 value).

Staffed by 12 SSI dive professionals, Ascuba Venture expertly acquaints aspiring aqua-explorers with underwater experience. Before strapping on the oxygen tanks, students attend three above-water classroom sessions to learn the basics of open-water diving. With newfound marine knowledge in mind, mermaid-impersonators then undergo a fitting session, where they're supplied with all the necessary equipment to make their first dive in Ascuba's heated indoor pool. The extended pool session covers both snorkeling and scuba skills, giving students a taste of what it's like to explore the unknowns of the Great Barrier Reef or the uncharted territories of Nessie's hot tub.

The Introduction to Scuba Diving program forms part of a complete certification course in open-water diving, a certification recognized around the world and on some parts of the moon. The full course involves three additional academic sessions and two or three more submerged sessions. The value of this Groupon may be applied toward the full certification course. On weekends, classes are on a schedule and walk-ins aren't allowed.