MobaSSH is a free SSH server for Windows, compatible with any ssh client (OpenSSH client, Putty, ...).
Windows version supported : 2000, XP, and now Sever 2003, Server 2008, Vista and Seven
MobaSSH comes with an easy to use installer and some useful GNU utilities for monitoring and managing a remote computer silently : bash, grep, gawk, top, vmstat, rsync, vim, ...
MobaSSH is packaged in a small single executable that registers as a Windows service so that it can be monitored like other normal Windows services.
MobaSSH will help you administrate / monitor / backup your Windows computers as you would do with Linux/Unix ones. Of course, MobaSSH can be used to transfer files securely in a SSH tunel thanks to the scp/sftp protocols.