Favorite Resources for Developing on HoloLens

A question I struggled with as a I started to develop for HoloLens is where to find information. There are not a lot of good sources of development information since public development only started about 6 months ago and the community is very small. The first place I would recommend is Microsoft's official resources:

• Windows HoloAcademy - Very out of date, but all the concepts are still correct, a good starting point
• Windows Holographic documentation - This is kept current and has great information not available elsewhere
• Official HoloLens Forums - Very active community but hard to get answers on the tough questions

Unofficially there are a couple other very good resources:

• Unity 3D HoloLens Forum - This forum is less active but tends to do better with the tougher questions
• HoloDevelopers Slack - Created by Jesse McCulloch this is an active community with great discussions, my favorite place to discuss HoloLens Development
• Stack Overflow - A bit of activity is starting here, but small compared to the activity in the forums above
• My HoloLens Tutorial - Still a work in progress, but I am aiming to make it the most complete and up to date tutorial available

Do you know of a great source of information that I missed? If you do, please let me know in the comments!