There's loads of great stuff at Aldi! Sometimes the produce might not be so great because the employees don't do turnover the same way other grocery stores do. You can get cheap as **** avocados and peppers there, and I can rely on them to alway have Brussels sprouts. The only produce I ever really had a problem with was onions - so take a sniff and a squeeze (ha!) before buying.
They have good deals on a variety of sauces (I regularly stock their soy sauce, both red and green sriracha, and their stir fry sauces), always have interesting flavors of hummus, and a bunch of cheap name brand snack alternatives for when I make Chex Mix. Don't bother with their baking chocolates, but their bar chocolate is supposed to be really good - it's from a chocolate place in Germany that's been producing since like 1900. And nuts! They have good deals on nuts and seeds!
They have good deals on frozen veggies, sugar that's not processed with animal bone char, and this week, they're supposed to have rip offs of Shun knives for $8 (a regular Shun chef's knife would run you $150+). All of their almond and soy milks are a good deal, too, and the canned beans/tomatoes/etc are a good deal, especially since you can get a bunch of that stuff in organic for cheap cheap cheap. No word on whether their meat or cheese prices are good or whether the product is good, I don't buy that kind of stuff.
There are always rotating special items each week that are only available for a short amount of time, and those things are usually really good, too. It's like a bare bones Trader Joe's (Aldi South is Aldi, Aldi North is TJs) - cheap in-house brands that are quality, and rotating trendy/seasonal things, with a surprisingly receptive finger on the pulse of food trends. I can take $20 into Aldi and come out with the stuff I need, and a buncha cool, fun things to try out. I think Aldi's great.