The leak: $360 a year
The plug: The average family of four uses about 1.6 gigabytes of data a month, according to Billshrink.com, though many pay $90 for 8 gigs. Track your usage to see if you can make do with a $60, 2-gig plan.
Nervous about overages? Use alerts or apps to keep tabs. Carriers have their own apps, or try DroidStats Android (free) or DataMan for iPhone (99¢).
Plug those small expenses that add up over time. See which of these money leaks apply to you and start saving hundreds - or even thousands -- a year.