I recently released Lightning Shell, a service to book access to a docker container with root access using Bitcoin's Lightning Network. It's meant for people who want to try out possibly untrusted software without polluting their system. In a future iteration I could also imagine self hosting Apps that book containers over an API, but that's still far from becoming reality.
Back in September I attended the 3rd Lightning Network Hackday in Berlin organized by fulmo. It was a rather loose gathering of people working on all sorts of Bitcoin and Lightning related projects. One of the most fun applications of Lightning I saw there was a little electronic candy dispenser. The concept was simple but yet fascinating: a Raspberry Pi, embedded in the candy dispenser, ran lnd and served a website with an invoice displayed as QR code. Every time one sent money some M&Ms dropped out of the machine and a new invoice was generated. This turned out to be so much fun that I decided to build one myself.