bottleO is a new plugin I've written to let players store xp.
The reaction when I announced it was very positive so after some bug testing (thanks volunteers!) ttk2 has uploaded it to the server.

The source code is available on github.
Please report any bugs you find on the Issues page.

A brief guide in how to use bottleO:
Right click on an enchanting table with glass bottles in your hand.
The plugin will then consume as many bottles and as much xp as you have (whichever is smaller) and place that many bottle o' enchanting items in your inventory. If your inventory is full, the remaining glass bottles in your hand will be replaced with the exp bottles.
These bottles stack to 64 and work like a splash potion, when thrown they spawn an xp orb.
The cost of making 1 bottle is 25 exp, and 25 xp is spawned when you throw the bottle.
For more information on xp, read the minecraft wiki page.