I do along with Alexa and Shopmium -- which are very similar apps offering the same coupons as coupons.com. I also use other rebate apps like Ibotta, Shopkick, Fetch Rewards & Swagbucks. Some less used rebate apps include Checkout51, Merryfield, Tada.
I use two coupons.com accounts, one for printing coupons off the web site and the other for rebates with the app. The other account is in my BF's name. I do couponing at Walmart and CVS for pretty much sundries only.. useless to me for food since most couponing food is processed junk.
Here's a thread I started a month ago:
https://forum.mrmoneymustache.com/ask-a-mustachian/couponing/EDIT: It's kind of fun to be able to try out new products without any cost associated with them -- so far I've been paid over $60 to collect $750 in free sundries. I really like the Love Planet & Beauty shampoo & conditioner as well as the Olay moisture ribbons body wash. Also, since I am attempting a $0 yearly discretionary spend, the hardest part of this self imposed challenge wil be: not being able to buy gifts; so being able to give each person like a couple hundred dollars in sundries for Christmas or birthday, at no cost to me, will be helpful to me with this challenge, as well as useful to the recipients. :)
EDIT #2: This hobby is very time consuming especially at the start -- since putting together the best deals can get complicated. Eventually I want to get it down to 8 hours of work each week to collect around $200 worth of stuff for free.
(This work includes researching the deals, putting together the deals, traveling to the stores in one big round trip, acquiring the items, prescanning the items with phone to make sure they will in fact work with the deal, the complicated checkout process, followed by the submission to multiple rebate apps and finally the bookkeeping involved with my personal finance software -- I track every penny.)