There was a very short mention of unicyclists on the Downieville Gathering web site. The Downieville Gathering is a weekend of riding for the two wheeled cycles.
Here is the web pagehttp://www.paradigmhosting.net/downieville03/index.htm >
Here is the quote: (Not much of a mention. But hey, I thought it was interesting.)
What kind of bike do I bring? Whichever one you want to bring. There’s something for everyone, from the shuttle monkey to the unicyclist (I literally saw a group of them riding the DH last summer…nuts!). Put it this way though, the typical “Downieville bike” (if there is such a beast) is a 5" trail bike with biggish pinch-flat proof tires and a front derailleur. But I’ve seen everything out there on the trails, and anything is appropriate. But, bring tubes, tubes, and more tubes if you are prone to pinch flatting.
Looks like they saw John Foss and the gang last year.
There is also some general Downieville information on the web site too for people thinking of Muni weekend this year.