key

Syntax: key \<character\>
Syntax: key temp \<character\>

'Key' allows a player or everyone to visit you at any time, regardless of 
whether you are on the game or not!

If 'key' has no arguments it will show people in your list with that flag
set.

If the first argument is 'temp' the flag will only last until you log out.

This command is a toggle.

See also: help showlist, help check and help keyring