Everybody get out your copy of Let It Bleed and get your ya-yas out in comemmoration: Tomorrow marks 38 years since the Rolling Stones-based disaster of the Altamont Speedway Free Music Festival. Those of you who remember it should officially begin feeling old…now.

If there’s anyone who by now doesn’t know the sordid tale of what happens when you cross a free Rolling Stones concert, 300,000 rowdy young fans, and a security force composed of Hell’s Angels (who were paid for the event in beer), here’s a sample from the Gimme Shelter documentary.

[youtube:http://www.youtube.com/watch?v=jY6yYAlueUM]