Do estimates make you slightly crazed? Maybe you want to roll your eyes at the organization's confusion between your estimate (guess) and a commitment. You're not alone.
I wrote an article about estimation, How to give IT project estimates—and when not to estimate at all. If you've ever struggled with estimating work, give it a read.
You might also want to read Predicting the Unpredictable: Pragmatic Approaches to Estimating Cost or Schedule.