They have a few great things you can't get anywhere else. Their
Applewood ham is great - I think they may only sell it around Easter time though. Also their Lite and Fit (I think that's the name) food is very good and relatively inexpensive. Grandessa fudge (only available at Christmas time though) is sooo good too. Cheap produce, as Dawn said, too. And many times their discontinued items go on a clearance aisle and that's always fun.
Mostly generic foods - many dairy items very cheap. Milk was like 1.49 a gallon there the other week. I think it was originally a German company, not sure if it still is.
Watch out for the lines though - usually very long lines, and oh!! bring your own bags - they don't come with your purchase. You can usually find a box to put your stuff in (you have to pack it yourself) and they sell paper bags and plastic ones there too.