It's always fun to mine with others, but sometimes you lose each other, and other times you might fight over who gets what loot. Hopefully, this will pose a solution.

Features:

Buddies can freely teleport to one another.
Buddy PvP is off, no more accidentally hitting your buddy with your pickaxe while mining
Config option for a 'warm-up' on the teleport command (Set to 0 to ignore).
Config option to only share ores (Coal, Iron Ore, Redstone, Gold Ore, Diamonds, Glowstone Dust)
Buddy Chat
Buddy Item Sending
Buddies share lott 50/50, always
Permission nodes for general use and all other commands, plugin will default to all players being allowed if permissions isn't used

Commands:

/buddy ~ Tells you who your buddy is, who you you have sent a BuddyUp request to, or who has sent you a BuddyUp request.
/buddy select ~ Allows you to hit another player (no damage caused, don't worry :P) to send them a BuddyUp request.
/buddy leave ~ Leave your buddy.
/buddy tp ~ Teleport to your buddy.
/buddy chat [message] ~ Chat privately with your buddy.
/buddy send ~ Send your buddy the item stack in your hand.
/buddy help ~ Lists and briefly describes commands.

Permissions:

BuddyUp.use ~ Allows general usage of the plugin.
BuddyUp.tp ~ Allows a player to teleport to his/her buddy.
BuddyUp.chat ~ Allows a player to chat privately with his/her buddy.
BuddyUp.send ~ Allows a player to send his/her buddy items.
BuddyUp.* ~ Gives a player full access to BuddyUp's features.

Configuration

Use Permissions: false Whether or not to use permissions nodes. If false, all players can use BuddyUp
Share Ores Only: false Whether or not only valuables are split 50/50 between buddies
tpWarmUpTime: 0 Amount of time "/buddy tp" warms up. Set to 0 for no warm-up.

To-Do

Allow loot sharing be enabled/disabled for individual buddy pairs
Allow loot sharing options to be tweaked for individual buddy pairs
Make "valuables" list configurable

BuddyUp