The PopVase is one of those things that we wish we'd thought of. It's so basic and so practical.
It's a waterproof vase, handmade from recycled-content paper. It folds up until you need it, and after you pop it open, fill it up with water (it has a thin laminate coating inside), use it, then you just fold it up again. Hmm. We could use it when we take flowers to someone in the hospital. And when we travel, and want flowers in our hotel room. And when we buy flowers at the farmer's market but don't want to leave them in the car to wilt while we go off for coffee...
It's biodegradable, too.
$21 for a pack of three at eco-artware.com.