MobaXterm - Enhanced terminal for Windows with X11 server, tabbed SSH client, network tools and much more
TeamViewer - TeamViewer lets you establish a connection to any PC or server within just a few seconds.
PuTTY - Popular free terminal application. Mostly used as an SSH client.
mRemoteNG - mRemoteNG is a fork of mRemote, an open source, tabbed, multi-protocol, remote connections manager.
ConEmu - ConEmu-Maximus5 is a full-featured local terminal for Windows devs, admins and users. Get better console window with tabs, splits, Quake style, copy+paste, DosBox and PuTTY integration, and much more.
join.me - Instant screen sharing. Instant Aha!