My friend is organizing a brony con called Running of the Leaves. It's taking place in Colorado this fall, starting with a Halloween party on October 31, followed by a whole weekend-plus-Friday of con.
The events include several dance parties, a music video contest, and improv, mock debate and karaoke games. There will also be video and tabletop gaming, and the obligatory dealer's room.
Check it out: Running of the Leaves - Colorado brony con