Weights-Measurements
Links
A Dictionary of Units of Measurement
http://www.unc.edu/~rowlett/units/index.html
"For information on a specific unit, click on the first letter of its name:"
Online Conversion - Convert just about anything to anything else
http://www.onlineconversion.com/
"Convert just about anything to anything else. Over 5,000 units, and 30,000 conversions."
Weights and Measures
http://www.merck.com/pubs/mmanual_home/appndxs/app2.htm
Merk's Guide to Weights and Measures.