TeamViewer - TeamViewer lets you establish a connection to any PC or server within just a few seconds.
mRemoteNG - mRemoteNG is a fork of mRemote, an open source, tabbed, multi-protocol, remote connections manager.
Splashtop Remote Support - Remotely support your clients’ computers and provide them with remote access
join.me - Instant screen sharing. Instant Aha!
BeyondTrust Remote Support - BeyondTrust Remote Support is remote desktop access, service desk, and collaboration software for Windows, Mac, Linux, iOS (iPad, iPhone), and Android devices.
Chrome Remote Desktop - The easy way to remotely connect with your home or work computer, or share your screen with others.