Madison Sporting Goods via eBay offers the Mongoose Men's 27.5" Seek'r Mountain Bike, model no. R4156WM, in Grey/Orange for $139.99 with free shipping. That's $10 below our mention from last week, the best deal now by $50, and the lowest total price we've seen. This 21-speed aluminum bike features a suspension fork, Shimano derailleur, twist shifters, front and rear disc brakes, and platform pedals.