Turn a Canning Jar into a Travel Mug with Cuppow
Cuppow is a silicone drinking lid that converts any wide-mouthed canning jar into a travel mug. Canning jars are sturdy, heat-resistant, easy to clean, and cheap, but their wide openings don’t make them a travel-friendly mug. Simply replace the seal with the Cuppow, screw the ring back on, and you have a eco-friendly cup that [...]
Source: http://the-gadgeteer.com/2012/01/28/turn-a-canning-jar-into-a-travel-mug-with-cuppow/