LAS VEGAS
Las Vegas Strip
(877) 847-4858, www.visitlasvegas.com
Visitors annually: 38.9 million
The house may always win, but don't be afraid to pull that lever: In Nevada, it's mandatory that video slot machines pay a minimum of 75 percent on average. Plus, what happens in Vegas … well, you know the rest.

LONDON
Tate Modern
011-44-20-7887-8888, www.tate.org.uk/modern
Visitors annually: 4.9 million
Although it's been open for less than a decade, Tate Modern is already a powerhouse tourist attraction in London. To accommodate the unexpected crowds, the museum has plans to construct an extension that will expand its size by 60 percent.

MIAMI
Miami Beach
(305) 604-2489, www.miamibeachfl.gov
Visitors annually: 10 million
Known as a hot spot for the young, rich, and famous, Miami Beach is a prime place to peoplewatch. Fashion shoots and the filming of movie scenes are common here, so you never know who might saunter by as you're sitting in the sun.