A Devival is when SubGenii get together and we have ourselves a ho-down. Even Wikipedia knows about Devivals! More fun than a root canal!
Devivals feature many acts, such as anti-music, frop smoking contests, and trained prairie squid. For info on upcoming devivals in your galaxy, please visit subgenius.com or consult your pineal gland. The biggest Devival of the year is, of course, X-Day. Here is a very long video showing an actual Devival: