2. PRIVATE JUMBO JET. Private jets are getting bigger and bigger. But none can compare to the "VIP A-380," a pimped-out version of the hulking A-380 super-jumbo. Saudi Prince Alwaleed bin Talal bought an A-380 to outfit as a private jet but before the jet was completed, it was sold to another user. It's unclear whether the new buyer is a company or person, and whether it will be used for personal or commercial purposes.
Still, the designer Edese Doret created a special design for Alwaleed's plane, called the "Flying Palace," which was never built. It featured a 14-seat dining table, a glass chandelier, and a "magic carpet room" that has a transparent floor to see the views below. Alas, the whirlpool tub never made the final cut for the design.
Theoretical price tag: $500 million.
(Read more: Priciest car ever sold at auction)
3. LAND YACHT. The world of luxury mash-ups— submarine-yachts, mansions in the sky—wouldn't be complete without a land yacht. Rest assured, the folks at Marchi Mobile brings us the "eleMMent Palazzo"—a 45-foot bulbous giant of a recreational vehicle that includes heated floors, a massive master suite, a rainshower and loads of marble. It's also got a roof-top terrace and driver's seat cockpit that's more like a jumbo-jet cockpit.
Price: $3 million.
—By CNBC's Robert Frank. Follow him on Twitter