if you're on a wireless lan playbooks can share files to pc so I'd expect something like ghost commander or ES File explorer or any other file explorer which can access windows / samba shares would work and unlike the web browser can be password protected
Pretty sure ES File Explorer will do it if you're on the same network and have wifi file sharing enabled; ES should see the other playbook as a samba share...
I gave that app an honest try but it seems pretty buggy. It likes to crash.
I generated an HTML directory listing and used that as index.html. It crashed. So I attempted to access videos directly using ip address:8080\videoname. That worked only half the time, and every time I tried, it would take a long time for anything to happen. If I stopped the stream, the app would crash. This was Playbook to PC, mind you.
But yes, it does work... just not reliably. The other posters are correct.. ES File Explorer is your best bet if you're streaming Playbook to Playbook.