These neoprene KegSkins work just like smaller bottle and can versions, sliding over a standard-sized keg and keeping it cool for hours:
In a lab test, two 38-degree kegs were subjected to an 80-degree environment for over five hours. The insulated keg only warmed six degrees over that period (44 degrees F is still plenty frosty) while the unprotected keg heated nearly 20 degrees in total to a flattening 57 F.
In addition, KegSkins don’t require electrical outlets like kegerators or hauling around tubs of ice. KegSkins are available in six color varieties, and can be customized with a picture or logo for an extra $10.