These mugs are popping up at popular restaurants for a wide assortment of drinks as a double wall aluminum vac sealed chamber. Weight is about 6 ounces for the one I have. They are great for coffee and other drinks with a large capacity and you don't have to guzzle to keep it cold or warm. I was looking at it as reasonably indestructible. Don't need a coffee warmer anymore for cyber hiking.
http://www.vat19.com/dvds/stainless-steel-beer-mug.cfm