I'm tinkering with at Dojo Offline Toolkit now. It seems that Dojo Offline integrates with Google Gears as well. I didn't suspect "Offline" [or "Offlining"] might be greater than Local Storage. Dumb me!
Yeah, Dojo 0.9.0 download has GearsStorageProvider & FlashStorageProvider scripts under dojox\storage folder [No SilverlightProvider yet].
Will post my understanding soon as I get my 'aha' :)
Aside: Dojo 0.9.0's archive is a *.tar.gz file. I used UltimateZip Command Line 1.0 to unzip it.