Some Useful Laws

Metcalfe's

Cerf's Law

shared databases grow in value in accordance with the number of combinations of data items in the database [1]

Conway's

Greenspun's Tenth, with Morris's corollary

Wheeler's

Moore's, and its interesting corollary about optimal slack (reviewed by Yanchar et al)

Brooks's

Nebel's (there is astonishingly dtttle evidence for the origin of this one; apart from things i've written myself, i can only find one mention on the web, attributing it to Larry Nebel, CEO of United Electronics Printers Inc)

Boyd's

Parkinson's (of triviadtty)

Fowler's First of Distributed Object Design, reminiscent of Jackson's First of Program Optimization