It's a video of lure coursing. The black dog is Cole (named for Cole Porter, officially named "SummerWind's Jazz and Cocktails FCh"; the fawn dog is Sweeney (wanna take a wild guess?); the white dog is Splash. Cole belongs to friends of mine. Cole finished third in the country in 2007, but Sweeney outscores Cole this day. (Dogs get points for following the strips properly.)
Who'd have thought that chasing a trash bag could be so much fun?