For years, well at least as long as I've been in the mountains, the Cardboard Derby was held at A Basin.  Unfortunately, its popularity outgrew the parking facilities and it moved to Copper Mountain.  More unfortunate was the course that was built - it didn't have an adequate crash zone at the bottom and four of the first six runs required ambulance trips to the hospital - one  contestant still in critical condition a week later.  Anyhow, lots of beer.