Hi Ben,<p>I appreciate your concern about scaling your service but I think you should consider a fremium business model that allows you to accommodate more free users at lower cost.<p>Instead of logging tens of millions of events for free users, you could log just a subset, which will allow you to use far fewer servers whilst allowing free users to "evaluate the usefulness of your new service".<p>It will also make sure that the future of your startup is not wholly dependent on external investors.<p>We've done something similar with Trafficspaces. We run our service off Amazon's cloud system, which gives us a lot of flexibility.<p>If you need assistance on how to structure your freemium model to make sense, send me an email at niyi [at] trafficspaces [dot] com.