Overstock.com offers the Sennheiser On-Ear Wireless Headphones, model no. RS120, for $56.99 with free shipping. (Amazon charges the same.) That's the lowest total price we could find by $12, although we saw them for $2 less in December. These open-back headphones feature a wireless transmitter that acts as the headphone charging dock. It includes two AAA NiMH rechargeable batteries.
Best Buy offers the Sennheiser HD 558 Headphones for $79.98 with free 2-day shipping. That's the lowest total price we could find by $55, although we saw it for $5 less a month ago. These open circumaural headphones feature a 15Hz to 28kHz frequency response, gold-plated 1/4" jack, and internal sound reflector.