Near Nottingham.
Yeah. A slow cooker is awesome for turning the cheapest, roughest cuts of meat into something quite delicious. However you would have to buy one (which surely wouldn't be cheating) first, but they're only like a tenner or so. Chuck a bit of cheap, tough beef in there, add a glass or two of cheapo red plonk, a hearty spoonful or two of gravy granules, some rosemary, oregano, basil, soy sauce, and then leave it on 'high' for about 3 hours. Don't put anything acidic such as tomato in though, though of course feel free to add afterwards. Chuck your veg in about half-way through, your carrots, onion, any root veg.
Your reward will be a lovely and nourishing meal that's big enough for a few servings and is highly nutritious (although you do near-boil away a lot of nutrition from the veg, you retain the water itself, unlike when just boiling veg normally). You only need to clean one, easily washed pot. It requires absolutely no attention whilst cooking - I never bother stirring mine, after initially 'preparing' it, beyond adding veg later. It uses less electricity than a regular cooker. Lots of recipes online for some really interesting dishes - I've eaten a slow-cooked lasagne before. It was pretty darn good. Not tried any of that meself though. It's also extremely inexpensive - you really do want the cheapest, toughest cuts of beef, pork, lamb or similar, a decent cut will be wasted and probably just fall apart compeltely in there.
Important note: a slow-cooker can NOT be used to make a
perpetual stew, and I've seen really nasty sickness befall someone who I used to live with, who thought it doable. Although you'll get multiple servings from your slow-cooker, I would suggest you freeze what you don't eat, and then simply reheat it the next day, in a saucepan, adding a small amount of extra water, and cook until well mixed.
Everyone has suggested lots of good ideas. I'd just like to repeat the suggestion of checking out 'ethnic' shops. In Wolverhampton for example, all the various asians shops all sell
huge drums of rice, cooking oil, maybe other things - and for cheap (by volume). I'm not massively keen on rice or I'd have been a regular shopper of such things.
If you use any veg, and you aren't going to use it all, freeze the rest. I rarely use a whole onion or bell pepper, and whatever's left can be neatly popped into a plastic bag and frozen. Similarly, I sometimes will make a *massive* batch of ragu, and then distribute it amongst several zip-lock bags, which I then freeze*. It's the most cost-effective way to make masses of yummy sauce, and only needs tinned tomatoes, herbs, possibly a little cornflour for thickening (if you have any). Again, looking up recipes online is your friend. Then, as others have said, go crazy with the cheap pasta.
Don't buy chicken. It's the most wasteful and awkward of meat. Check out the clearance section in all of your local supermarkets - unless this would be cheating, you can find lots of fine food that simply has a slightly dented can, or because the product range has been deleted, for cheap. Don't be afraid to buy frozen or tined veg (or meat). As others have said, a little olive oil and seasoning can sometimes be all you need to make a tasty meal. Don't buy tomatoes, they're too expensive and unless you buy the more expensive kind, they're usually shit, in my opinion. Buy tinned tomatoes. If you like a tomato on your sandwich or salad - what the fuck are you doing eating salad, you rich git?
* picked up this tip from my former-culinary student girlfriend. It's obvious in hindsight, of course.