What I find amusing is all the talk of "extreme couponing" like it was something new. Nope, just better PR in the 21st century, what with the internet & reality TV shows
Something very similar was quite popular back in the late 70's, early 80's. Most people referred to it as Couponing & Refunding. Articles in the "ladies" magazines, pen-pal type groups to talk about it, etc.
One aspect back then was the "refunding" part - manufacturers would offer refunds in newspapers, magazines & in-store, to send in so many proofs of purchase and get something back. Sometimes you got cash, sometimes you got merchandise, sometimes awesome coupons to use. Before tossing out a box or label of anything some people would clip off the parts commonly used as "proofs of purchase" (boxtops, whole can labels, etc) and file them by food type or brand, as well as keep all register tapes in case they were needed as well. So if an offer was made that required six soup labels, you might only have to go buy one more to have enough to get the refund. Articles showed people who had not just cabinets but whole closets or more of file folders full of labels, etc., sorted by brand or type of food, etc. Some would get by the "one per household" restriction by using variations of their names, combined with the addresses of friends & family or even post office boxes.
Since a lot of the "refunds" were actually special coupons (free items at the stoer, or extra large discounts), there were lots of magazine & newspaper articles showing the shopping trips where they'd get huge amounts of groceries for tiny amounts of cash. Same as now, pretty much. Back then, though, lots of grocery stores would double all coupons, or some had certain days they would double or even triple coupon values. If you combined an item on sale, with a tripled coupon, especially an extra large coupon you got as a refund, and bought the size that with a price closest to the total value off, you really could get items for a fraction of the cost.
I did some of it, nothing too obsessive - I had one large file drawer I kept for labels & so forth, & probably spent 2 - 3 hours a week clipping, sending off for things, and so forth. My daughter was little, so her holidays were suplemented with some cute promotional stuffed toys, colouring books and so forth. And I saved probably $100 a month or so in coupons & cash refunds (my "me" money that I stashed without the now "ex" knowing).
It can definitely save you some money if done right, and it can be fun. But it can also take up a lot of time.
My advice is to keep these things in mind - some of which have been brought up by others, of course.
Decide how much time you want to spend doing this, and stick to that (based on how much spare time you have, how badly you need the money, and whether you love it or hate it).
Be nice about it - research & accept store policies, if you have a lot of coupons or complicated combinations, go when crowds are low, and warn cashiers (and thank them for the extra time & trouble.
Find ways to trade coupons you can't use for ones you can - some supermarkets have boxes you can leave them in, or ask people you know - trading baby item coupons for pet coupons can help a lot if you dont' have kids but have a dog or cat. Even if you don't trade, leaving ones you can't use in a box at a supermarket or library is a nice gesture.
Don't forget to figure in gas costs as well as time, if you have to go to more than one store, or go to a store farther away. And the cost of newspapers, magazines, etc. if you buy them only for the coupons.
Don't buy what you can't use - you aren't saving any money if you don't use the product. Exceptions, of course, are if you know someone who will use it, give it to a food bank, etc.
Be realistic about what you can use before it goes bad. Half a dozen boxes of cereal could probably be used before the best-by dates, half a dozen jars of something with a shorter shelf life, maybe not. Be realistic on sizes, as well, it isn't a savings if you have to buy the largest size to use the coupon, and end up tossing half of it out when it goes bad.
Be realistic about your storage space - if it gets damp or bugs, you've wasted money or time, and if it inconveniences other family members, it may not be such a bargain.
Be realistic about what you're actually saving. If you get a snack food practically free, it might be nice, but if you wouldn't have bought the snack food without the coupon, it isn't really savings, it's an extra freebie.
Be realistic about nutrition & tastes. Eating something not as good for you instead of something healthier because you have a coupon is questionable on nutrition, as are big savings on high calore items if you're trying to lose weight, etc. Also, how important are savings if you push your family to eat brands/flavors or even types of foods they don't like? On the other hand, though, an almost free coupon can be a great chance to try a new product or brand for the first time.
Take what you see and read with a grain of salt. Sure, the person in the article or on the TV show or internet may have gotten $100 of products for $2 - but they may have put hours and hours into clipping, searching, etc. to do so. They may also have been saving those coupons for months to be able to do that, and can only repeat it once or twice a year. They may not actually be able to use all those products, or use them before they go bad. And it will almost always show only items they had great savings on, which could be mainly extras & un-needed items, leaving their normal weekly shopping of necessities pretty much unafected.
Figure out if it's worth it for you, and go for it to the extent that works for you. I've heard people say why spend two hours a week clipping coupons to save $5, that isn't good return of money for your time. But then, if you sit and clip coupons while watching TV one evening, using time you wouldn't use for something else or get more money for anyway, and don't mind it, then why not?
I don't do too much couponing these days for various reasons, it just doesn't quite fit in or isn't worthwhile right now for me. But I do try to keep an eye out for the bargains & coupons I come across. I find the local freebie mailbox inserts have a lot of buy one, get one free deals on fast food. They come in handy when no one wants to cook, especially when we can use them to get take out sandwiches, and have our own drinks at home. Maybe not so nutritious, but we do like a fast food fix now and then