HTCondor is developed by the Center for High Throughput Computing at the University of Wisconsin-Madison (UW-Madison), and was first installed as a production system in the UW-Madison Computer Sciences department more than 15 years ago. HTCondor pools have since served as a major source of computing cycles to UW faculty and students. For many, it has revolutionized the role computing plays in their research. An increase of one, and sometimes even two, orders of magnitude in the computing throughput of a research organization can have a profound impact on research size, complexity, and scope. Over the years, the project, and now the Center for High Throughput Computing have established collaborations with scientists from around the world, and have provided them with access to many cycles. One scientist consumed 100 CPU years!