To prove I have no interesting news:

I have a double walled drink tumbler I really like. The place for the straw has a little crosshash you push the straw through like on a McDonald's drink, but it's made of rubber and makes a perfect seal around the straw. When the straw is removed a spring loaded plug flips up from underneath and plugs the straw hole. So it really doesn't leak. It also keeps drinks cold a long time.

@poemblaze Brand? Where'd you get it?