Forever Bags from Menards a few weeks back. They were one of those "Pay $4.00 and get a $4.00 rebate back" type of deals. Due to the frequency of my trips to Menards, I usually take a flyer on these things because I can typically spend the rebates on something I actually want.
The Forever Bags folks claim that these bags will extend the life of your produce by somehow removing the ethylene gas that gets produced. Take a peek at those bananas above. The one of the left was left out normally. The two on the right were in the yellow bag.
I was skeptical, but the proof is in the photo: they actually work. Do they keep your bananas perfect? Nope. But, might they extend them by a few days? Seems that way.