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An interesting topic!
I started collecting after my first repair of a G4 Ti PowerBook that held particular sentimental value.

Link HERE.

From there the interest just flourished, adding other interesting models and refurbishing if/when required.
A number of my acquisitions have a tale behind them, some of which I've shared in the past with posts on the PPC forum. Five such links below:

Collection overview: HERE

My rare SE 466MHz Key-Lime 'twins'

The iMac 'twins'

The rare 'Kanga'

The chauffeur-delivered 'TAM'
 
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