In the final moments of the first GW2 Beta Weekend Event, Team Legacy decided to crash the server before Arenanet could shut them down. Watch as the magic unfolds.
For reference: This is two sets of Mesmer portals placed on top of each other. Each time the loop is setup, you'll notice many people in chat suddenly complain of lag. I'm sure they'll fix this for the next beta, but it was still fun :)