LG seems to be leading the way in combining Bluetooth headsets with other things. The LG Decoy, for example, was one of the first cell phones to have a built-in Bluetooth headset in the back. Now at CES 2009, LG has introduced the LG HBM-800, a Bluetooth headset and speakerphone in one. This isn't new--we've seen this before in this Kyocera Portable Speaker--but we can't think of many others like this one.
On its own, the headset is like any other Bluetooth headset. It has dual microphones for echo cancellation and noise suppression, plus it has LG's e-Clip ergonomic earbud on the back. Once you dock the headset into the speakerphone however, the audio automatically transfers to the speakerphone, and you can now use it like you would a Bluetooth speaker. This also works in reverse; when you take the headset out, the audio will transfer to the headset. The speakerphone has a clip on the back so you can easily clip it to your car's visor. This is a great option if you want both a Bluetooth speakerphone and a Bluetooth headset in one compact package.
The headset's talk time is up to 4 hours while the speakerphone/cradle talk time is up to 7 hours. No word on price or availability.