Purchased: From your Guild Lord
What he/she does: The party master would be able to do a variety of things that pertain to holding a party in your guild hall.
My guild's 1 year aniversary is fast approaching, and we want to have a fun drop party, or "race to the drops" sort of game. Well as we were trying to figure out how we could possibly do this, we realized that we can't, unless limiting the size of our party (as in the celebration) to 16, in which we would use a Scrimmage. Also, during a scrimmage, there are *many* NPC's in the way of the fun.
So for one of the Party Master's abilities, he/she would be able to collect items from players. The Party Master's Vault would appear just like a storage, except it would be MUCH larger (like infinite). At an appointed time (which can only be changed by a guild officer or leader), the party master begins dropping a few items every five or ten seconds.
Any player can add an item to the party vault. NOBODY can remove them. One idea is that you could only remove items that you put in. I assume this would be specific to character, not account. If in the first case, you would be asked if you really wanted to add this item to the Party Master's Vault.
Additional things would be Fireworks, purchasing decorations for your guild hall (could be seasonal or year round, and could last forever, or could only remain up for a week or so), and other games.
Games would be either in the form of team games or all vs all. In Team games, a scrimmage type match would begin. In all vs all, a game counter and score much like the ones during the Dragon Festival 2006 would begin. At the end of every game, a winner is announced. The person who pays for the game to begin would also be able to set a cash prize for teams, or a cash/item prize for all vs all games.
Game ideas:
Balloon Pop - Try to pop as many balloons as possible (pick up the balloon). Team with the most balloons wins. Balloons would only spawn at the center area of the guild hall.
Suicide Bombers - Both teams have one skill, Self Destruct. This skill kills you and all nearby foes. The object of the game is to claim the Obelisk Stand by having as many people stand near it as possible (like in Alliance Battles). When both teams are on the stand, the only way to win is to die. ^_^
Help me get more game ideas if you like the idea.

Note: I apologize for having three topics all posted within one hour on the same forum, but I have just been sitting here brewing on these.