S3 seems great today, and is undoubtedly more <i>technically</i> reliable than any home solution, but history is littered with companies that closed down on very short notice leaving their users&#x27; data deleted or inaccessible. Not to mention that billing disputes or legal action could also affect your ability to get data from them.<p>(Jason Scott is speaking from experience here, as one of the people called in to do emergency archive response when these cloud businesses shut down.)<p>Edit: jacquesm points out the sudden death of cloudspaces.com, which I&#x27;d forgotten about: <a href="http:&#x2F;&#x2F;www.infoworld.com&#x2F;article&#x2F;2608076&#x2F;data-center&#x2F;murder-in-the-amazon-cloud.html" rel="nofollow">http:&#x2F;&#x2F;www.infoworld.com&#x2F;article&#x2F;2608076&#x2F;data-center&#x2F;murder-...</a><p>A single computer security problem (which happen on a daily basis, although not usually at this severity) could enable your cloud to be deleted.<p>The &quot;counterparty risk&quot; is small but ineradicable. The finance industry re-learnt this with Bear Stearns recently.