So got a crazy home project that you've been meaning to do? Well go price the project out. Try to see if there are any alternatives you can use like Oops paint or a different material. I love finding clearance items or returned items to use!
Also if you are doing a major project, break up the purchase into small transactions. You can buy it little by little and use smaller, better coupons! I have a few $5 off of $25 for True Value. Home Depot takes competitors coupons so I will use it there and save quite a bit of money by buying the materials in small chunks.