Can you add additional storage to the Gateway system? If so, what hardware works and how does it install?
Yes. You need an eSATA external HDD enclosure and HDD. (Shaw PVR Expander Guide) You can buy one from Shaw (Limited to 1TB) or build your own. (Up to at least 6TB that I can remember off hand.)
I use this external enclosure + 1.5TB HDD.
There are other enclosure options including RAID. (6TB+) Different forum, but useful info: Shaw Gateway: Adding External Drives
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