Calling someone without allowing him to pick up the phone - disconnecting after a second, and not paying a cent.
This can signal something you agreed upon (such as: letting him know you're at his house ready to pick him up), or maybe you're just cheap.
(it already has a term in Hebrew, widely used)
<Sound of the first-second of the Star Wars theme>
<Sound of a Nerd going down the stairs, picked up by his super-nerd-friend>