It love this excellent design from Joshua Resnikoff and Aaron Panone, the
Cuppow. Turn any canning jar into a travel mug by replacing the seal with this BPA lid and screwing back on the retaining ring. Brilliant, simple design and execution. I also love that it's easily adaptable to both small and large containers depending on your need (of course that was
Ball's doing making the mouths of their canning jars one of two sizes). It is available for $7.99 from
cuppow.com
CUPPOW! from Paper Fortress on Vimeo.