Bottle o' Enchanting

The Bottle o' Enchanting, also known as the Experience Potion is an item which can be used to spawn experience orbs.

Obtaining
A bottle o' enchanting cannot be brewed, but can be acquired by trading with a villager priest. This is the only way to obtain one on survival, without cheats. Priests will offer 2–4 bottles o' enchanting for one emerald. Villager priests can be found randomly in villages.

As of snapshot, villagers will no longer offer bottles o' enchanting.

Usage
A bottle o' enchanting can be thrown like a Splash Potion. On impact with any object (except for air, lava, and water), it will drop experience orbs worth 3–11 experience points. The bottle o' enchanting breaks on a variety of different surfaces and objects that may not be expected, including mobs and blocks that players can pass through, such as active portals.

Farming (Pre-1.8)
Since this item is tradeable with a priest, it is also a very good form of an XP farm. All you need is a good sugarcane or wheat farm and get emeralds. Then trade the emeralds for as many Bottles o' Enchanting that you need. A stack of them will give you between 192 and 704 EXP; giving you between 11 and 27 levels if you were to start from zero. To get the full stack requires a lot of sugarcane/wheat (between 384, best case scenario and 1,120 worst case scenario, for sugarcane; and between 288, best case scenario, and 672, worst case scenario, for wheat). If you choose to trade with sugarcane, simply turn it into paper and trade a librarian for an emerald.

Those are just the best and worst case scenario for each, you will find librarians and priests who want any value in their respective ranges. i.e., the min number of paper a librarian will want for his emeralds is 24, and the max is 35; you could get a librarian that wants 25, 34, or 28 paper for one emerald. The same goes for how many bottles you could get for one emerald from a priest. i.e., a priest will give a min of 2 bottles per emerald, and a max of 4 per emerald, but it could still give 3 per emerald. See the page about trading for more information on the values during trading.

Trivia

 * Even though the bottle o' enchanting is green, it gives off blue sparks, and glows purple (as an enchanted item does).
 * Throwing multiple bottles o' enchanting on the ground while flying and then falling will cause the screen to go green/yellow and play the experience sound for sometimes minutes at a time.
 * This can also happen if the player dies with a large amount of experience orbs because the XP flies around the player, making these lights.
 * Repeatedly throwing bottles o' enchanting will create many experience orbs on the ground, which can lead to a noticeable decrease in the FPS rates of players somewhere near the experience orbs. Thus, this can be used as a form of griefing. However, this would mean one must acquire many bottles o' enchanting, which may be difficult in survival mode.
 * When placed in a dispenser, the bottle o' enchanting is treated as a projectile and fired similarly to arrows, snowballs, fire charges, and eggs.
 * This item is the only potion style item in glass bottle shape that can be thrown.

Gallery
Erfahrungsfläschchen Fiole d'expérience Fles der Magiërs Zaklęta butelka Зелье опыта