From my 5 year old daughters ice skating recital last weekend. Some very tough lighting conditions. Pretty much spot lights only that were floating around her group of 12 skaters while she was on the ice. Had to follow somewhat blind until she got one of the two spotlights and then click click click.
Canon 40D - Canon EF 17-40mm f/4 L - Canon EF 24-70mm f/2.8 L- Canon EF 50mm f/1.8 II - Canon EF 70-200mm f/4 L - Canon 430 EX II Speedlight