I've found this to be handy for handing remote desktops:
It supports RDP, VNC, VMRC, RAS, Telnet, SSH, ICA Citrix.
Comes with many other networking tools like Ping, Trace Route, DNS Resolver, etc.
So far, this is my choice, although there's bugs on and off.
The others listed here are for reference, which some might found it handy for its simplicity.
It supports RDP and VNC.
It supports RDP, VNC, SSH, Telnet.
It supports only RDP.