Perhaps during my scouring of the forums I missed this suggestion, but here goes anyway;
I’ve recently been dropping things off for people on roads outside their builds (that we’re all villagers to) and just now I had the simple idea of a mailbox system.
You place a mailbox within your beacon that anyone can deposit into, but only you can take from.
People would be able to remove the items placed in there themselves, but not the items deposited by other players.
Great idea. Delivering actual mail would be neat too (like letters)
Excellent idea. I love it. It would definitely be used.
Many MMOs out there already have this system, it becoming kind of a norm. I think WOW popularized it.
They are planed
Sorry to necro the old mailbox topic. Posted it to the wrong thread 
Awesome. Thanks @Jeffrotheswell. Glad to see someone can use the search function better than me.
Yup, Donation Box is planned, but there is no recipe for it yet.