I love it when people say it takes too much time to save money. What you don't sit in front of the TV ever? That is where I do it. I clip on Sundays when I get the paper and then I match Sunday night to the local ads. I usually shop Sunday night too (these shelves are usually stocked then).
I save at least 50% off my grocery bill every week sometimes more. So is it worth it to me to clip coupons, the short answer is yes. I sometimes purchase specific ones from Ebay as well.