They even made one of the few Windows NT on MIPS workstations. The RM 300 could run either SINIX (a Unix variant) or Windows NT/MIPS.
http://www.katalog.iser.fau.de/index.php?ort_id=322&inventar...
http://www.katalog.iser.fau.de/index.php?ort_id=322&inventar...
SINIX and Linux used the R4000 in big endian mode, whereas NT was running in little endian. You had to flash a different firmware to switch between the systems...