On http://www.b9.com/elect/avr/kavr...
From the ChangeLog:
Version 1.13 (Feb 20, 2008) - Fix error in Timer calculator when entering a desired frequency of 0 - Fix off-by-one error in TCNT Base - Change Timer "Requested Timing" numeric value with changing timer units - Rework display of Baud calcuator to better visually group related fields
Edit: Update subject