Also, can I drop a package in one bufferbox and have it delivered to another?

You want to borrow my snowboarding helmet, goggles and gloves. I drop them in my box, select a destination, and buffer box teleports them to your box. Reverse the process when your done with it. Also, I let it be COD - meaning that you, the borrower, pay for the round trip buffer transfer cost.

You mean like a post box?

I have never seen this process work with a post box. Please package in box SFO-03-01-AA and select it to be delivered to NYC-12-02-AC.

While the logistical process is the same, its much more like an inter-office mailstop than it is a post box.