I can say air, water, food, and sleep. But obviously the context of the question is to mention objects we’re very attached to. The things I take with me everywhere are my keys, my glasses and my phone. Special mention goes to my wallet, my watch, my sunglasses, some cap, a couple of bracelets, and cologne. You can say I’m pretty boring, since those are the same objects most people carry when they leave the house. But I still have to mention one more item:

I don’t leave my house without any one of my collectible knives.