Wallet, smartphone, headphones, 36 oz water bottle (topped off), keys if I'm driving somewhere.

Oh, and I double-check to ensure I'm fully (properly) clothed and wearing my glasses. I've definitely made it as far as my car, before realizing I'm still wearing pajama pants.

And my vision is not that bad, so I can roam my house without glasses. But once I hit the open road, I suddenly realize I can't see anything.

When I was in the military, I used to carry a multitool (eg. Leatherman) on my belt everywhere I went. But now that I'm a retired civilian, it just causes problems if I need to explain why I have a knife on me.

Even though it's a multitool, everyone just sees it as a blade. And I'd rather not have someone confiscate it. When you're wearing a military uniform, no one questions it. But I've definitely been stopped in some stores because I was carrying it in civilian clothes.

My wife also bought me a lockpicking set, but I don't know how to use it yet, so I removed it from my keychain. No sense carrying it around if I can't use it. Maybe once day...