So I found this article about the Barn Hunt.
For years, informal barn hunts were held in conjunction with earthdog
events and terrier fun days, using various rules, and as something to
enjoy with no pressure on handler or dog. But these informal events
were never a sanctioned sport. The Barn Hunt Association, LLC has
created a sanctioned sport honoring the traditional role of dogs in
ridding barns, homes, and properties of vermin. Barn Hunt opens this
fun sport up to any dog, of any size, type, breed or mix that can fit
through an 18″ wide through approximately 22″ high tunnel. In Barn
Hunt, you can earn titles and placements at levels from Instinct
through Master, and even Championships and beyond.
Also for more info Barn Hunt is a fun and exciting new dog sport. In
Barn Hunt, dogs hunt for rats hidden in a straw bale maze. It's a
timed event, with levels of difficulty from Novice to Master. There
will be ribbons, placements, and titles. Fun tests are already being
held across the country and there is tremendous interest. You can find
out much more about the sport by going to the Barn Hunt Web Page. Barn
Hunt is growing rapidly in popularity. Join our facebook page and
yahoogroup . Look above at the Events link to find fun tests, trials,
training, and judge workshops; and at the club locator map to find
clubs in your area. We want to hear from you!
http://gogetfunding.com/project/barn-hunt-dog-sport-startup On this
webpage there is a video that you can look at.
(this answer is a repost because it was deleted by it's owner... but the info is good so I don't want it to be lost)