Abstract-In the past year we have gained experience in custom computing by porting a number of large applications to Teramac. Teramac is a custom computer capable of executing million-gate user designs at speeds approaching one megahertz. Teramac includes software that fully automates the conversion of high-level user designs to configurations that are ready to run on Teramac. Two applications, both in excess of a quarter million gates, are described here: an artery-extraction filter that locates and highlights arteries in medical MRI datasets; and Cube, a volume-rendering engine. We have discovered the importance of scalable, parameterized designs. We have been successful in parameterizing some aspects of our designs and we have identified improvements to our tools which would facilitate further parameterization. Our users have benefitted from the speed at which their applications run on Teramac and have gained confidence in their designs after seeing them run on actual hardware.