EmailSherlock

A reverse email search conducted at EmailSherlock.com can help determine the identity of the owner of an unknown address that shows up in your inbox. You can also use this free email search service to learn more about an address you found in your address book or perhaps in connection with an online ad you're considering responding to.

Now with this handy Chrome Tool, you can right click any email address and directly search it on EmailSherlock.com or select any text and the Email Sherlock will find the email address in the context and show you the direct search box for it.