A fairly well-used pair of Sennheiser wireless headphones. Excellent for any purpose where a wired connection is problematic - I personally used them at the office.

Note that they are RF headphones, not Bluetooth - this makes interference a bit more likely from things like WiFi points, but they do have channel selection to get around that.

Sample review and more details here: http://www.audioreview.com/cat/headphones-home-audio/wireless-heaphones/sennheiser/hdr-130/prd_458373_7799crx.aspx