https://paribus.co/I came across this service through one of the financial websites.
Basically they scour the major online retailers for price drops for anything you buy. If the price drop is within the price match guarantee period they apply for the refund in your name. When you sign up you put in your credit card info to receive the refunds.
They take a 25% cut but it's reduced by the number of other people you sign up. And no, I'm not asking anyone to use me as a referral.
As an example, we buy a lot of items through Amazon's subscription service. Yesterday I got a notification that Paribus discovered a 32 cent price drop on the cat littler we buy. Since we buy four bags a month we were entitled to $1.28 refund minus their commission.
I also received notification from Amazon about the refund so I know it's working.
Of course, this wasn't exactly a huge deal but still, it's found money and it's painless. Needless to say, it would be very rewarding if you made a big purchase.
Just thought I'd pass it on.