Quick tip: Sometimes you need to signup for a service with an email address to confirm the user registration. When that time comes, it’s a good idea not to use your personal email.
You should take a look at 10 minute Mail, a service that generates a 10-minute email account for you.
NOTE: there are tones of 10 minute email services out there. The one linked in this article is just an example. If you want to use a different service just search for 10 minute mail in your favorite search engine
NOTE: also check out throwawaymail, which gives you a 48-hour inbox. Or until you clear your cookies.