We conducted an experiment with 30,000 users of a virtual nanotechnology facility, nanoHUB.org. We investigate the effect of virtual points and message framing on user participation in a survey. In one treatment, users receive points for completing the survey. In another treatment, users are exposed to a visual observation cue. We vary the social message, either emphasizing the private benefit to the user or the social benefit to the community of participation. Participation rates are increased through virtual points and for users receiving the private benefit messaging. The observation cue doesn't have an effect.