John Burk had the awesome idea for the Physics Teacher Camp this summer - a professional development opportunity without any lame PowerPoints or a thousand talks that you passively listen to. He brought a dozen or so physics teachers together at St. Andrews in DE for four days of... whatever we wanted to do.
The balance between freedom to pursue what we wanted and the availability of collaborators made it the most productive and fun thing you've ever called professional development!
I made a few WCYDWT? videos, but I haven't had the time to polish and post them yet (soon, I promise!). Apart from that, I got a bunch of great ideas for lab practica and general pedagogy. The amount that you can grow by being in prolonged contact with other excited physics teachers with no other tasks to perform can't be overestimated!
John and I did, however, write an article about it in for the October edition of The Physics Teacher. The permalink is here, though you'll need a subscription to TPT to view it.