Buy.com offers the Canon EF 40mm f/2.8 STM Pancake Camera Lens, model no. 6310B002, for $149.99 with free shipping. That's $41 under our August mention and the lowest total price we could find by $49. This 0.3-lb. lens is for use with most Canon SLR cameras.

Update: A reader notes that Beach Camera via Amazon offers the above lens bundled with a kit for the same price. It includes a filter, cleaning kit, memory card holder, and lens cap keeper.