ADB was a great connection and died a sad death.  The last mac to have an ADB port was the B&W G3 tower.

I have read on xlr8yourmac.com that OSX only likes ADB if its built in to the mac and adapters are sketchy at best.
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Mac mini C2D 1.83GHz - 2GB RAM - 200GB 7200rpm HD
Sawtooth w/G4 1GHz - 1GB RAM - SIIG SATA w/2x1TB HD
B&W w/G4 600MHz - 1GB RAM - 2x80GB HD
Sawtooth G4 400MHz - 512MB RAM - 40GB HD
Dell Ultrasharp 2007WFP 20" Widescreen LCD
2.94TB Total Storage