Serum - VST for FL Studio, Ableton Live, and many other VST supported DAWs. Heavily utilized in EDM.
FullContact Card Reader - Automagically scan biz cards into LinkedIn/Gmail contacts
Surge XT - Open-source subtractive-hybrid synthesizer formerly sold commercially as Vember Audio Surge.
Truecaller - Find a person by a name or phone number worldwide for free using Truecaller.
Omnisphere - Piano, pad and synth VST for DAW's.
Google Contacts - Google Contacts is Google's contact management tool that is available in its free email service Gmail, as a standalone service, and as a part of Google's business-oriented suite of web apps Google Apps.