My hourly rates differ according to the assignment: Longer assignments get cheaper rates, writing specifcations is more demanding than programming according to fixed specifications, and a project manager takes on far more responsibility. I try to attain a reasonable rate for a reasonable assignment, and relate to the research (in German, sorry) “IT Freiberufler – Honorare – Kosten – Marktbedingungen” by Stefan Rohr and Heinz Streicher, ISBN 3-920560-08-6.