Bukkit

Each force field can now have multiple owners! The owner that placed the force field is the only one with the power to add and remove owners. They can also change the owner. Every owner can walk through the force field.

ForceField now supports Factions. If a player is in a faction when they create a force field then the admin of the faction is automatically set as the original owner. If the only owner is the faction then anyone in that faction can go through. If any owners are added then only those players can go through a force field. When a player joins a faction all their force fields come under control of the faction.

By placing diamond, iron, gold, or emerald blocks plus zero or more extensions players can create force fields that other players cannot walk through. Once one of these blocks is placed and a player right clicks on it with a diamond sword it becomes the base for a force field generator. Players can then add up to 6 additional blocks on the faces in order to increase the range of the force field. The force field is formed as a cube with each block contributing to the radius of the cube from the base.

Diamond blocks default set at 10. configurable
Gold blocks add default set at 5. configurable
Iron blocks add default set at 3. configurable
Emerald blocks add default set at 7. configurable

The item needed to create a force field is now configurable. Default to diamond sword.
The ability to blown up force fields is now configurable. Default to true.

Explosions do not destroy blocks inside a force field unless the explosion would have destroyed the base of the force field. In this situation the explosion would have the normal area of effect. Mobs and players can still be killed by an explosion inside a force field.
configurable. If boomDampe is true then it cancels explosions. otherwise it doesn't. Default is true.

If a player walks into a force field that did not create it, lightning will strike but won't do damage.

Spherical force fields will be created if enabled in the config. In the config if cube: true the force fields will be cubes. cube: false will make them spherical.

Force fields will be prevented from being created if the force field would intersect another force field. The creation of extensions is also limited in this way. Force fields also are forced to be created with at least one space in between force fields so players can't completely block of spawns.

Permissions:
forcefield.reload:
description: Allows a player to reload ForceField.
default: false
forcefield.create:
description: Allows players to create forcefields.
default: true
forcefield.destroy:
description: Allows players to destroy forcefields.
default: true
forcefield.use:
description: Allows players to build or destroy forcefields.
children:
forcefield.create: true
forcefield.destroy: true
forcefield.server:
description: Allows server related forcefield actions.
default: false
forcefield.bypass:
description: Allow player to walk through anyone's forcefield.
default: false
forcefield.throughserver:
description: Allow players to walk through server forcefields.
default: true
forcefield.*:
description: Grants a user all ForceField permissions.
children:
forcefield.reload: true
forcefield.use: true
forcefield.server: true
forcefield.throughserver: true

Commands:
forcefield:
description: Allows access to ForceField commands.
aliases: force
usage: |
/forcefield reload - Reloads ForceField config
/forcefield who - Lists the owners of the force field that you are in.
/forcefield add [player] - Adds an owner to the force field that you are in.
/forcefield remove [player] - Removes an owner from the force field you are in.
/forcefield change [player] - Changes owner to the specified player. Doesn't work in Faction mode.
/forcefield list - Shows a list of all your force fields.
permission: forcefield.reload
permission-message: You don't have permission to do that.

Default Config:
diamond: 10
emerald: 7
gold: 5
iron: 3

boomDampen: true
cube: true
forceFieldTool: 276
boomDestroy: true

Delete the old config.yml to get the new one with all the potion effects listed. By default they are all disabled. Just uncomment each effect that you want to be applied to players when they are inside a force field.

If any of these don't appear in your config.yml add them manually or delete your config.yml and the default one will be created.

To Do List (in no particular order):
I'm open to any other suggestions as well!

Known Bugs:
All players in a force field gain the potion effects even if they aren't owner. (Fixed in next release.)