Collectinator
Scans your mini-pets and mounts and provide a check list for what you're missing.
Download for
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Cataclysm
-
The Burning Crusade
-
Wrath of the Lich King
Cataclysm 
The Burning Crusade 
Wrath of the Lich King Addon Details
Expansion
Categories
Developers
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Provides methods for determining which mini-pets and mounts you are missing. Open up your companion window (pets or mounts) and click the scan button. This will open up another window which will allow you to see which companions you are missing, along with how to acquire them.
Download Collectinator
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