US unicyclists recently held their North American Unicycling Convention and Championships. There are loads of videos circulating on YouTube about the event. Here's one compilation:
http://www.youtube.com/watch?v=o9djGzZuXZY
but also check out the high jump (highest jump cleared 125 cm!): http://www.youtube.com/watch?v=NZCgPKSI7Bc