Book clubs have been a staple of traditional communities for generations. These can be used for online communities too.
Ask members to put together a list of 5 to 10 books most relevant to your sector. Every sector has books they admire. This can be your domain of knowledge.
Now go beyond this. Preview upcoming books, write to the publisher and get free copies to give away (this is easy, you’re doing their job for them), interview the author (usually not too difficult), have a live discussion based around the book, perhaps have a working group to assess how the book material can be applied, have reviews of the book and rank it amongst your communities recommended list.
My favorite moment of the year was interviewing David Chavis, author of the Sense of Community paper. I was shocked he agreed to do it.
Online book clubs are an easy way of generating activity. Better yet, the people you would love to reach, the people that would generate a lot of excitement and interest in your community, probably aren’t as out of reach as you imagine. It's worth asking if they want to be involved in your community.
p.s. Here is our summer reading for Community professionals (start from the top and work your way down).