Solspace has been developing ExpressionEngine based solutions for its own client base for more than 10 years. During that time we have had occasion to abstract our solutions into add-ons for ExpressionEngine. We make these solutions available to other developers so that they may bring their client sites up to speed more quickly and easily. In many cases one can purchase a group of add-ons from Solspace for a few hundred dollars and by doing so save many thousands of dollars in development expenses and many weeks of project time