Very popular free SSH client. Connects to hosts via secure shell, telnet or RS232. This program has been around for ages. It may not be the prettiest one, but it does the job and it is free.
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Pro Source code available
Full source available. Compile and modify it yourself.
Pro De facto standard client for SSH, Telnet and Rlogin
Con No global settings
If you want to change a setting for all your connections, you'd have to do it individualy.