Love my Konftel Ego portable bluetooth speakerphone. It stays plugged into USB power 99% of the time on my desk but the audio quality for myself as well as how others hear me is leaps and bounds better than any other solution I have found, including headsets.

Obviously if there are others in the room/house then a speakerphone may not be the best solution; but if you aren't going to annoy others I find a speaker phone far less fatiguing than dealing with headsets all day.