The Sennheiser CX-300 in-ear headphones ($60 street) are very small and fairly nonintrusive. If you liked Sony's MDR-EX series, these are even better: The sound isn't as thick, and they're more efficient. The bass is very powerful—maybe too much for some tastes—but it doesn't completely overwhelm the rest of the sound. For bass lovers and subway commuters, these listening devices are a very good step up from stock earbuds.