Connor is infamous for dropping his cups while in the van. And then they roll and I can't reach them while driving. I'd seen the Bottlelink, but haven't purchased them.
We already have the Inchbug Labels that wrap around the cups. See here for that post. I'm thinking I'm going to use those as well as the Bright Starts Lots of Links to connect the cups to the boys' car seats. Now, I know that the links come apart, so it's not fool-proof, but, it's materials I already have. Worth a shot.
A coworker mentioned these, which she has only found at Walgreen's. They are the No Throw straps; a 2-pack is $5.99. Might have to go buy those before our Thanksgiving travels...