PuTTY

a free ssh/telnet client, available at http://www.chiark.greenend.org.uk/~sgtatham/putty/

There are sister utilities that you can obtain from the same folks, which are:

1. PuTTY (the Telnet and SSH client itself)
2. PSCP (an SCP client, i.e. command-line secure file copy)
3. PSFTP (an SFTP client, i.e. general file transfer sessions much like FTP)
4. PuTTYtel (a Telnet-only client)
5. Plink (a command-line interface to the PuTTY back ends)
6. Pageant (an SSH authentication agent for PuTTY, PSCP and Plink)
7. PuTTYgen (an RSA and DSA key generation utility).