Most of my suggestions (Netflix, Hulu, menu planning, strict shopping, evaluating need v. want, bringing meals from home) have already been covered. One thing to note, however, is that you will often end up spending just as much, if not more, if you cut out your cable service--if that's how you also have your internet. Around here, packages with basic cable + internet are either less than or equal to just internet. (Ask me how I know.)
I find coupon shopping to be dicey. We used to do it, years ago; it's why we started getting the Sunday paper. But we've changed what we eat, and I really just don't find the coupons particularly useful any more. Instead, we buy certain things in bulk, and go with El Cheapo Brand for them (toilet paper, dish soap, hand soap, mouthwash, Windex, laundry detergent, etc.). I find that some cheap/generic brands are OK, while others are definitely not.
One thing that we spent some money on a while ago, but it's saved time and money in the long run, is to invest in dish cloths and a lot of dish towels. We have a lot of them. A whole lot. I keep them in a shallow basket on top of the fridge for easy access. This cuts down on sponges and paper towels (you already know my dislike of paper towels). For most things, it's just as easy to grab a towel or dish cloth to clean something up...and then we can just throw it in the laundry with other stuff.
Oh, and speaking of laundry, we wash everything in cold water and air-dry as much as we possibly can.
