Poor Man’s Yojimbo. Not readily apparent to most Mac users (myself included), the built-in Keychain Access utility is actually a great way to store secure passwords and even notes (didn’t know about the latter). If only there was a way to create custom categories in the left pane and sync with iCloud, it could probably replace Evernote for me.
BTW: Yojimbo is an exceptional information manager app for the Mac (and iPad), from the makers of BBEdit (my text/code editor of choice), but it costs money. Keychain Access is included free with every modern Mac (though is a lot less feature-packed and user-friendly).