Use group projects and group document management to help students collaborate. Even if students do not live close to each other, they can collaborate on group projects and learn about the different workplaces, experiences and cultures that they come from. Encourage students to use online document management systems like Google Docs to collaborate on group projects and edit them communally. Have students work on a project like a wiki together.
Add online discussion forums that complement online learning materials. Allow students to chat with each other, with teaching assistants and with workshop leaders in a casual online format. This virtual contact allows them to bounce ideas off each other, ask questions and behave like other students might when they go for a coffee after class. Let the online forum become a venue for informal learning and sharing, an activity that Moiseeva et al state is very important to building community.
Communicate in real time if possible. Use a scheduler like Doodle to set up times when students can meet through Skype or other teleconferencing or videoconferencing tools. Use these tools to allow students to do class presentations online or communicate in groups about a project. Hold a Twitter party or other online meetup to follow and discuss an emerging issue in the subject that the class is covering.
Customize the learning to the participants. As Kathleen Gilroy suggests, the onus for making Web-based learning worthwhile and useful often falls on the shoulders of the learners. The teacher and learners need to work together to learn about each other and discover what the learners want to get out of the course. This interaction allows the instructor to create a course and a community that work well for the participants and encourage participants to collaborate and participate.