Kevo
A prototype-based object-oriented language written for Macintosh by Antero Taivalsaari at UTA, Finland. Kevo is built around a threaded code interpreter and features a unique prototype-based object model (which is based neither on classes nor Self-style delegation), pre-emptive multitasking, cooperative multitasking, dynamic memory management, an icon-based object browser and editor modelled loosely after Mac Finder. Kevo's syntax is close to Forth and its semantics resembles Self and Omega.