A number of services are available these days which offer what they call throwaway email addresses. These are addresses that you use when you don't want to reveal your regular email address. Once they've served their purpose, you stop using them, so it doesn't matter if they get added a spammer's mail list.

An example of where you might use a throwaway address is registering to receive some file or information of interest by email, or to be able to download a file from a website. If you have to give them a valid email address, either because they're going to email the product there, or because they're going to email some access key, activation code, verification code to you, but you won't need to stay in email contact with them afterward, a throwaway address can be useful.

You need not create a new throwaway address every time you need a temporary address. Just use one until it starts receiving spam. Then switch to another.

If you can successfully keep your regular email address private, throwaway addresses can be an excellent tool to allow you to function online without getting inundated by spam.