Sennheiser CX300B 3.5mm Connector Canal Headphone for $14.99 after Rebate, Shipped Free!
 

For the money, I don't see any earbuds beating these Sennheisers. The CX300-B has some great reviews and they say that it has great bass and no mid range muddiness. The kicker is that you need to send in an old pair of earphones with the rebate. They don't have to be working.

• Get the Sennheiser CX300-B. SENNHEISER CX300-B EARPHONE SALE
  
  
• Here's the REBATE FORM