Microfortnight

English

Noun

A period of time equal to 1.2096 seconds, or 1/1000000 of a fortnight.

According to the The Jargon File, The VMS computer operating system has a lot of tuning parameters that you can set with the SYSGEN utility, and one of these is TIMEPROMPTWAIT, the time the system will wait for an operator to set the correct date and time at boot if it realizes that the current value is bogus. This time is specified in microfortnights!

See Wikipedia on Strange Units