I worked in the video game industry for 5 years. I knew all the top people, wrote regularly for relevant magazines, and understood the sector better than any newcomer could. It was relatively easy to develop online communities for different businesses within this field.
You can do the same. Pick a sector, become well known within it and then sell community building services to businesses within that sector. You have the solid track record, clear advantage over others and should charge a premium for the service.
I’d be happy to pay it.
Aside, hiring an existing community manager within the sector you’re developing a community for makes a lot of sense.