Another good article from IEEE Spectrum. I'm particularly interested in the disposable glider drone at the bottom, which is basically just a PCB with wings. (Because this comes from the research arm of the Navy, and is of broad technical interest to this community, I am make a sysadmin exemption to our no-military rule. I don't do it often.)
Here's a wild way to launch UAVs: by using a high-altitude weather balloon with a drone stapled to it, with drones stapled to it. Nope, that's not a typo: The Naval Research Laboratory has been using weather balloons to carry a medium-sized Tempest UAV up to 60,000 feet, and the Tempest UAV itself is carrying a pair of tiny little CICADA (Close-In Covert Autonomous Disposable Aircraft ) drones underneath its wings. Look:
The Tempest can travel up to 30 miles and deploy the CICADAs as gliders, which can then land within 15 feet of their target coordinates. Each CICADA can carry a variety of sensor payloads, and as the name implies, they're designed to be cheap and disposable: The airframe is actually just a custom printed circuit board.
This balloon launch multi-drone thing in particular is very cool, since whatever you attach to the balloon can use its engine purely for range as opposed to altitude. And dropping off these little microdrones to get in and do the dirty work saves a bunch of money and adds that much more versatility to the entire system.