If you ever thought previously mentioned Xobni looked cool, but you prefer Gmail to Outlook, free Gmail plug-in Etacts adds many of the same features. You get social information, conversation history, and advanced sending preferences right in your Gmail sidebars. The Etacts plug-in automatically adds detailed contact information to the sidebar of messages, as shown above, similar to previously mentioned Rapportive, but Etacts takes it one step further. Not only do you get links to any social networks that contact is a part of, and some of the information contained therein (such as their occupation and location), but you also get a detailed summary of your mailing history with them, complete with nice little graphs and charts. All this information is also available in compose mode as well, so you know exactly who you're sending it to. Read more: Lifehacker