Eschew Obfuscation! (Good Advice: Keep it simple!)
Fog Index: A measure of how difficult it is to read a paragraph:
Gunning Fog Index
Fog Index Calculator
Online Fog Index Calculator
Readability Test Tool
Readability Calculator
Readability Calculators - Edit Central
Fog Index-Calculator-Review and Improve Readability
Tech Head Fog Index
Two futures: mentions "Gunning Fog Index" and Flesch's Index
Comm300 Fog Index
Describing Gnu Program for Readablity
Fog Index writing tips
Word Police
Judges scold lawyers for bad writing

Fun if you play with Words
BS Generator Java
Buzzword Bingo

Nightscribe tried to "break" the above calculators by inserting a very complex 129 word definition.
The result was nearly grade 70 readability!!