Quote from caput_miner
/take [player] [im(item minimum), x, y, z, r] [item] [amount]
This would be the opposite of the /give command but it takes an item from the players inventory.
It is possible to make a store using command blocks but the only possible currency is xp levels. With this command you would be able to do it with any item you want. Like diamonds or gold for example.
But for the store to work the /give command would Have to have an im (item minimum) in addition to lm (levels minimum(which currently exists)) so you can only give people things if they have atleast a certain amount of a certain item.
I think this would be a pretty cool new command, tell me if you like it.
I like the new player target ideas, but the take command already exists in the form of /clear. If no item is specified, as you probably know, it clears the entire inventory, but you can also specify an item id (/clear <player> <item id>) and it will remove only instances of that item from the inventory. It does, however, take all of them, not a specified amount.