Temporary Email
Do you ever want to send or receive an email or two, but don't want your address ending up on an undesired mailing list? You might not know that there are 'temporary email' services freely available.
Guerilla Mail is one of these services. It's simple to use, you don't have to sign up or anything. Just visit https://www.guerrillamail.com and enter the email address you'd like for yourself (it will default to a randomly-generated one). From there, you have an inbox for incoming messages, and the ability to compose/send new messages.
Not recommended for anything personal or private—because anyone who knows your email address can see your inbox—but it's a nice tool for avoiding spam and keeping your PII away from others.