With Google Mail (and gmail) you can do things like name+geekzone@yourdomain.com - That is a way to be able to filter for email coming through on that address. You can also set up aliases and groups to forward emails and use that to filter.
So you can use your "best" address with a little extra thought and still give it to people you don't trust to not forward it to spammers.
Let's say you need to sign up for a mailing list that interests you, but you're afraid spammers might get your address. We'll call the list "exoticflowers". Sign up with the list using the address "johndoe+exoticflowers@gmail.com". Email to that address will still come to your "johndoe@gmail.com" address even though the "To:" will include that "+exoticflowers" in it.
Source: http://lifehacker.com/144397/instant-disposable-gmail-addresses