PuTTY - Popular free terminal application. Mostly used as an SSH client.
Microsoft BitLocker - BitLocker is a full disk encryption feature included with Windows Vista and later.
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.
Paubox - Paubox provides HIPAA compliant email encryption without the hassle of extra steps.
MobaXterm - MobaXterm is a software that uses a set of optimized network tools included in a single exe file. MobaXterm integrates several network clients with an X server, and also integrates a full set of Unix based commands. Read more about MobaXterm.
OpenSSH - OpenSSH is a free version of the SSH connectivity tools that technical users rely on.