Manage multiple email addresses.
If you use Gmail, useMail Plane App. It's the best!
If you use Mac, considerAir Mail. It's beautiful, organized, and easy to read.
If you're old-fashioned or want the tested and reliable, but don't care so much about how nice the UI is, useOutlook express.
Don't just give away your email address...
...until you definitely want to commit. When you sign up for a free trial, they will put you on their marketing mailing list and will send you many marketing emails.
It will generate a random email for you like this "firstname.lastname@example.org" which you can use for some time, then discard and generate a new one.
Automatic email tracking and other improvements
Automatic email tracking. Calendar integration. Chat messaging interface for simple replies. Etc...