So far I haven't seen a terminal server client for Linux, nor a ssh server for Windows...
"windows ssh server"
"terminal server client"
to see the variety of possibilies.
If you're running KDE:
From the KDE Help Center
Remote Desktop Connection is a client application that allows you to view or even control the desktop session on another machine that is running a compatible (VNC) server.
You would typically use Remote Desktop Connection with the KDE VNC server, which is Desktop Sharing, since it closely matches the special features of Remote Desktop Connection.
Works w/ Winders also.
From man rdesktop
From the Remote Desktop Connection Dialog box
Enter the address of the computer to connect to, or browse the network and select one. VNC and RDP compatible servers will be supported.
rdesktop is a client for Remote Desktop Protocol (RDP), used in a number of
Microsoft products including Windows NT Terminal Server, Windows 2000 Server,
Windows XP and Windows 2003 Server.
(to open KDE Remote Desktop Connection, run krdc
-> More Applicatons
-> Remote Desktop Connection
, at least in Simply MEPIS.)