Buyspry via eBay offers the refurbished Beats by Dre Solo HD Headphones in six colors (Lime Green pictured) for $79.99 with free shipping. That's $15 under our March mention of new headphones and the lowest total price we've seen for these headphones. (It's currently $20 below the lowest total price we could find for these headphones new.) They feature an in-line mic with controls and travel case.
A 90-day warranty applies, but it's unclear who backs it.