When I switched over to Netflix, I chose the three-at-a-time plan because my wife and I love to watch movies and catch up on TV series we have missed. We were already saving over our Blockbuster plan, and with the addition of Netflix's Watch Instantly feature, it seemed like the best choice.

After a few months, I decided to check out my renting habits using Feedflix.com, which calculated my cost per rental and other statistics about my Netflix subscription.

I knew I had been lax about watching and returning DVDs but I didn't realize that my cost per rental is an astonishing $8.49! More than double what I would pay at any local rental store. Thankfully my per-rental price drops to a more reasonable $2.55 after you take into account my new-found obsession with the Watch Instantly feature.

While I could cut back my subscription like my colleague Tom Barlow did, I am going to try to maximize my value using the alerts that FeedFlix provides. Now, I'll get an email every Tuesday if I have kept a movie more than five days. This will help me stay on top of rentals and make sure that I have something good for the weekend. If my cost per rental is still too high next month, I'll drop my subscription plan down a notch until I find a good balance.

FeedFlix is free and easy to try out, making it an excellent tool for any Netflix subscriber. Taking a closer look at one of my subscriptions has only reinforced the notion that we often overestimate the value of our subscription plans. I wish I could get a similar tool for my Gamefly subscription, since I have a tendency to keep games too long as well.