I know plenty of people either love or hate the behind the head styled headphones/headsets, but for me I think this Plantronics headset really sits nicely. The 645 USB is also one of the smarter USB headsets I've seen, with the USB acting as a dongle rather than an integrated element. This means you can opt to go analogue or digital, depending on what suits the machine you're on. The cable has in-line controls for volume and mic sensitivity (high, low, and mute).
Why USB? Maybe you've never encountered a computer with terrible on-board audio, but sometimes it is great to control the audio as a digital process rather than accept whatever the machine can handle. The best example on this front is gaming, where pro gamers will always use USB headsets. No matter what machine they sit down at, they know the audio I/O will be managed by their own drivers. The 645 USB is both PC and Mac compat, so no dramas there. At $59.95, I'd say they're a pretty good deal. [Plantronics]