One solution is the formation of CO2s (churches of two) within each larger house church. Another solution is the formation of a private Facebook group which allows the members of a house church to connect on a more regular basis.
We've also used Facebook groups as a way for the cohorts in the Foundation Courses (previously the Apprenticeship) to connect with one another. Many of us have been surprised at the level of comment that has developed in this context.
Rose and Desi Starr are house church leaders and cohort coaches in the Apprenticeship. In the video below, Rose shares what it has been like to be a busy mother of four little ones and still engage with her cohort on Facebook.