For a limited time Groupon is offering the 2-Pack of Logitech Ultimate Ears 200vi Noise-Isolating Earphones + Free Shipping. These generally sell for about $40 apiece, so this is a great bargain when you're getting two for less than the price of one.

Amazon reviewers have given these earbuds a solid 3.5/5 stars. (They're currently selling at a pretty decent $13 apiece at Amazon too, if you're only wanting one pair.)