World's most luxurious first class cabins

Singapore Airlines was the first carrier to unveil the gigantic, double-deck Airbus A380 and devoted plenty of the extra space to their first class passengers.

Singapore Airlines offers not just a comfy seat, but a full "suite," which can be closed off from the aisle by a pair of sliding doors.

Best of all, the center divider between the suites lowers, allowing couples, or spendthrift singles, to enjoy the comfort of a double bed.

The price, naturally, is very steep. One-way flights from Singapore to London start at around $13,000.

The price, naturally, is very steep. One-way flights from Singapore to London start at around $13,000.

The price, naturally, is very steep. One-way flights from Singapore to London start at around $13,000.

Singapore Airlines might have been the first to take to the skies in the massive A380, but Dubai-based Emirates might well claim to have used the space a bit better. The ultra-luxurious carrier offers similar suite-style accommodations, but adds a rare in-flight shower spa. The spacious, windowed restroom offers the first shower on a commercial flight. Granted, bathing time is limited to five minutes, but at least the airline can be the one finally making good on the claim of its passengers arriving "refreshed."

Status-minded first class passengers—and, at these prices, there are many—would do well to book a seat in Etihad Airways Diamond Class. Also carried on the jumbo A380, the premier suite-style seating offers a small seat, facing the main lounger, so that couples can share a meal over the burl wood fold-out table. The primary seat, which folds down into a flat bed, also boasts message functions and a universal charging port. No shower here, but plenty of luxury, as well they should be, considering the five-figure one-way price.

Cathay Pacific, the Hong Kong-based luxury carrier, have not yet chosen to upgrade to the ultra-wide A380, and thus must make do with refitted 747s. By traditional first class standards, this cabin is first rate, and sports a soothingly modern look. Business travelers, rather than couples, seem to be the target market, with single, cocoon-like seats dominating the seating chart. In other words, luxurious, but rather standard. That is, until passengers disembark in Hong Kong, where the recently renovated lounge offers ridiculously opulent amenities, like private, glassed-in shower and lounge areas for each passenger.

Soon, the ultimate expression of luxury travel, the Virgin Galactic space plane, will make its inaugural flight, sending six lucky travelers at a time into zero gravity on the edge of space. The $200K fare buys a round trip from the New Mexico launch pad in the highly stylized cabin of the SpaceShipTwo. The interiors of the rocket-powered plane haven't yet been finalized, but mockups and concept drawings show reclined loungers set amid a relatively spacious cabin with multiple portals for maximum space viewing.