Spotted via Andrew Baron's tweetstream, this fascinating — no, really! — snopes article on why Van Halen had that line in their concert rider about ABSOLUTELY NO BROWN M&Ms EVER.
Punch line: the true reason behind this had to do with technology, engineering, and safety issues. But I can kind of hear David Lee Roth delivering the lines in his over-the-top screamy-voice when I read his quotes. Actually, I can hear David Lee Roth's voice when I read the rider.
Snopes.com: Van Halen Brown M&Ms. The actual 1982 rider was first published online at smokinggun.com in 2008.
Video below: "Jamie's Cryin," from David Lee Roth's bluegrass cover album of VH hits, remixed by a fan in a homebrew video with (why not?) a Popeye cartoon. You can buy the record here if you are so inclined: Strummin' With The Devil: Bluegrass Tribute to Van Halen.
Update: JKD says,
Also, a recent episode of "This American Life" also had a segment on
the brown M&M clause, and the general dynamics of touring and
contracts, with John Flansburgh from TMBG: