Continuing on my No-Name Experiment, I've tried many, many products and several of them are now staples in our cupboard. As was pointed out in the comments ages ago, things that are the simplest tend to be the best, or to make little difference.
I have found that beans of all kinds (Chic Peas, Black Beans, Romano Beans, Pork n' Beans) are fine (though sometimes have more salt then I'd like).
Tuna, bottled lemon juice, canned tomatoes and tomato paste (both salt-free!) are great, just as good as brand name.
I am a huge fan of No Name perogies. G is a HUGE fan of perogies, so we eat them at least once a week. We were surprised at how good the No Name brand was. We had eaten some Cheemo brand recently (Feta, Spinach and Potato flavour) and those were amazingly good, so the No Name ones didn't live up to those, but they were as good as any other standard potato/cheese ones I've had. They have become a staple in our fridge.
I believe someone mentioned ketchup not being worth it, but I haven't found much of a difference. I don't buy Heinz ketchup ever since I went to Mexico and saw small children picking their tomatoes, so I probably don't know what I'm missing.