13 Mini Beauty Miracles That Do It All

Crest 3D White 2 Hour Express Whitestrips

These give you results comparable to what you'd get at the dentist's office—minus the co-pay (or time spent clock watching in the waiting room). The layer of peroxide on the strips whitens teeth in two hours, and results last up to three months.

$55 for four doses, Drugstore.com