In fact, I think the best method is to get your own domain, set up Google Apps for you domain. Then you can set the catch all address, and for every website you need an email address for, you use <website>@<yourdomain>.com (eg amazon@example.com and msdn@example.com.

Email to amazon and msdn addresses would autoforward to your catchall address - if you found that msdn was spamming you too much, then you can just mark anything coming in on that address as spam. (if their unsubscribe didn't work, that is.

It's a great way to find out who sells their email lists (or has had them stolen). "doostang.com" is a great example of this - I receive a ton of spam from other companies based on the email I used on their website.

Just FYI.