On a stock Mac OS X system, you only know Time Machine is backing up when you hear your back-up disk start churning and see the Time Machine menu extra's icon start spinning.
This app polls the system log looking for messages from Time Machine, and translates them into Growl notifications for back-up started, back-up finished, and back-up canceled. The back-up started notification tells you how long since the last back-up finished, and the other two tell you how long the back-up ran for.
At least one user reported that TimeMachineGrowler's initial search of the log took an unknown but very large amount of time. The bug, if indeed there is one, is in the log-searching mechanism of Mac OS X, so there is nothing I can do about it.
MD5 and SHA1 signatures were created using EasyHash.
I've created a Google Group where you can report problems and/or receive notifications of updates.
This project used to be hosted in a Mercurial repository. The old Mercurial repository will never again be updated! It is frozen forever at 1.0.2. If you want to follow changes or contribute changes yourself, follow and/or clone the Git repo.
I provide TimeMachineGrowler—the application, and its source code—under a three-clause BSD license. For more information, see the file named LICENSE.txt that comes with it.