For family crap I'm always assigned to get beer. I don't have a great palate, but it's better than the rest of my relatives who, I swear, would just get bud light.
For friends I bring a cheesy potato casserole that one of my aunts always cooks for our family get-togethers who I made give me the recipe. None of that corn flake crap, and shredded potatoes not the disks or whatever. I didn't like it at first because I don't normally like sour cream and it has that in it, but I grew to love it and my friends do too (or who knows, maybe they just tell me that, but it's always gone at the end of the meal). I've thought about starting to bring a huge thing of baked mac and cheese since it'd be easier to make, but haven't done it yet and we only really do it twice a year.