Jaunted

· Roman Abramovich: The Russian oligarch famously owns several submarines, from a two-person recreational sub which may or may not still be housed onboard his yacht Pelorus, to a getaway sub on his newer boat, Eclipse.

· Paul Allen: Microsoft's co-founder is extremely secretive about his sub(s). Nonetheless, there are some known details about one, like the fact that it's yellow, 40-foot-long with a $12 million sticker price, space for 10 passengers and "enough extras to remain submerged for a week." You'll find it (or rather, only Allen will find it) inside his 416-foot yacht Octopus.

· Larry Ellison/David Geffen: Billionaire secrecy continues as we can only say that Ellison—the CEO of Oracle—had "space for a submarine" built into his 452-foot-long yacht Rising Sun, which also boats a large indoor swimming pool. Ellison recently sold the yacht to David Geffen, who may or may not now also be in possession of a sub.

· Unnamed Emiratis: Of course some dudes in the United Arab Emirates have personal subs. Because of non-disclosure agreements in the world of sub-building, however, little to nothing is known about who actually owns them and how big and fancy they are, although since Dubai loves only superlatives, that they're likely very fancy.

[Photo: Virgin Oceanic]