That's the beauty of the method I use. Nobody sees the name+xyz@gmail account. In fact, they don't see Gmail at all. They see xyz@mydomain.com which is forwarded to [email protected] behind the scenes.
And with my host's control panel, it's not hard to mass edit all my forward-only e-mail accounts to change the forwarding address if my Gmail account finally is overrun with spam.
But let's put it this way: I've been using this method with my current Gmail account, which I've had for over two years now, and the only spam I ever get is an occasional newsletter from Xara, who just won't remove me from their mailing list.
-Deozaan
But what do you do if you DID want to reply to the sender (it wasn't spam)? Then they would know your address.
That is why I use
www.spamex.com which for $10/year gives me 500 disposable addresses. The emails are all forwarded to a real email address somewhere. And if I reply to someone, they massage the header, so the addresses I reply from doesn't show up. I can also send attachments up to 500k. I have a bookmarklet on my links bar for when I want to bring up spamex and create a new address or access the interface. Since the domain name contains the word spam, I have had some occasional problems with some ISP's refusing to forward mail to it. Which is why spamex also allows the use of the xemaps.com name (spamex backwards) :) I use spamex for all forum registrations, newsletters, etc.
I also have my own domain name where I have 2 addresses that goes to Outlook. Only very trustworthy friends/people/companies get these addresses. I hosted this through
www.addaction.com because I can use my own domain name directly in outlook (send/receive) or I can use their email servers (which is what I use since they allow me to use an encrypted connection, port 995).
I have other email accounts also, such as 2 gmail accounts (Gmail has been very reliable but since Google scans all email looking for keywords to generate advertising for you, one wonders just how secure gmail really is), a Yahoo account (never use, always full of spam), an inbox.com account (hardly use but can send 50mb attachments), mail.com (hardly use) and an account at safe-mail.net (this is where spamex feeds to. This account is always HTTPS but the free version only provides 3mb of storage. However, I've gotten maybe 3 spam emails here in maybe 4 years of use). Probably a few others lying around also...