Bukkit

What is the enhancement in mind? How should it look and feel?

Minecraft 1.9 Experience trade. Have players eligible to trade exp for money.

And player id's for signs.
Have a command called /duckshop id <name:optional> or something of the sort.
/duckshop id will return the player their id, for replacement as their name incase its too long
/duckshop id ralts will return that player's id for incase you want to check a sign b4 u buy.
Exmaple of a sign:
id:1
1 diamond
$100.00

I'm not sure about the ID numbers – it makes it slightly harder to figure out what the sign actually does – but the concept is interesting.

I'll look in to it.