XPConomy

XPConomy is a plugin that allows players to send other players levels of experience.

Commands:
Aliases: /xp,/exp,/experience,/xpconomy

/xp give command increases the <player's> xp amount
Usage: /xp give <Player> <amount>
Example: /xp give Notch 80

/xp send command increases the target's xp while decreasing the senders
Usage: /xp send <Player> <amount>
Example: /xp send Notch 20

Permissions Nodes:
xpconomy.* - Gives permission to all xpconomy commands
xpconomy.xp.give - Gives permission for the /xp give command
xpconomy.xp.send - Gives permission for the /xp send command

Changelog:
v1.0

• Basic exp trading, plugin Released

v1.1

• Added Permissions
  
• Changed /xp give <name> <amount> to /xp send <name> <amount>
  
• Re-purposed /xp give to have it give <player> the amount of xp without depleting the sender's xp. This command is console compatible
  
• Fixed a problem where a person could send a negative amount of xp, thus depleting the the other person's xp
  
• Added several command aliases (xp,exp,experience,xpconomy)
  
• Fixed a couple of errors

v1.1.1

• Fixed a problem where giving a player a negative amount of xp greater than their total, would set them in debt
  
• Fixed two more errors

v1.1.2

• Fixed error messages sometimes not showing up
  
• Corrected default permissions

Downloads:
DropBox Download:
http://dl.dropbox.com/u/33386148/XPConomy/XPConomy%20v1.1.2.jar

NOTE: Source code comes with the download

Known Problems:

A bug where people can farm exp by collaborating with another player:

Darkenvy said:

"Realize this: it takes 2 exp orbs to get to lvl one. however it takes around 20 to get from 49 to 50. you can have someone simply gain lvl 1 over and over and send the exp to someone else. This would only take 100 orbs to get to lvl 50 vs the several hundred required to get to lvl 50"

Thanks to Darkenvy for pointing this out. Please don't tell this to your players =P, I am working on this.