FogBugz is a bug tracking applicaiton from Fog Creek Software. Version 6 of FogBugz introduced Evidence Based Scheduling, and added time tracking fuctions to FogBugz to support it.
TimeSprite can exchange time tracking data with FogBugz. It uses the FogBugz API to send and receive information about cases and recorded time.
The TimeSprite FogBugz integration allows you to:

TimeSprite makes the FogBugz time tracking significantly easier to use.