Mac OS X runs Deleted Applications
From Pyile
Imagine that you trash an application because of a security flaw. Say, it handles the URL type foofoo, and is proven to be a security risk. But the developer won’t fix it (or hasn’t fixed it yet), so you’ve removed the application from your hard drive to keep yourself safe.
It doesn’t work that way — you’re not safe. Time machine has made a copy in your time machine backup that Mac OS X will cheerfully launch without a warning.
(Shawn's Comment: Thanks to Dan via our mailing list for the heads up on this)
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Use Time Machine for docs and prefs only.
Better to back up the system and apps to a disk image via Super Duper or Carbon Copy Cloner.
I'd be dubious of trying to restore the system via Time Machine, so I'd rather not back up that way.
Having said that, Time machine does sound good for documents and preferences (the "Users" folders), and when I get a new hard drive and Leopard, I'll be using Time Machine to back up my user folder.
Shawn Levasseur
Rockland ME
http://ComicsPundit.com