Found: Bicyclick Click-Stand Handlebar Gadget to Keep Your Bikes Upright
Bicyclick’s Click-Stand and Click-Base use a simple ball and socket connector stuck in the ends of any flat handlebar to keep two bikes connected and standing on their own.
If you’re riding solo, the Click-Base mounts to a wall (cubicle or fixed) and lets you pop your bike against the wall without fear of it falling over accidentally. The system weight is just 49g and supposedly installs in just a couple minutes. We’re waiting to hear back on price and availability, but if you wanna get on their list, check ‘em out here.
UPDATE: Sets run $25 for the Bicyclick and $15 for the Click Base. A combo pack is $37, and multipacks and family packs are also available for a bit of a discount on the per unit price.