Nowadays some (older?) fans of black metal, death metal, gothic metal and the like are not averse to a bit of luxury. Since 2007, the organisers of Wacken Open Air (W:O:A), an annual heavy metal festival in Germany, offer attendees the chance to rent a personal mobile toilet. Costing 120 Euros each, there are 150 MMWCs (Metal Mobil WCs) on offer. The MMWC provider will clean your toilet too, for an additional 25 Euros.
In 2011 all 150 personal toilets were booked within 4 hours, according to the festival web site.
The vast majority of the 80,000 festival goers will still have to queue, as usual, in front of the public mobile toilets available for free on the festival site.