If you are programming and using C++ I might recommend the following links:

vim - and not its girlie cousin Vim -g, gvim for those who still don't get it. Emacs is ok I suppose but keep in mind the following list of tools can be done from inside of it...with LISP implementations of course.
tin - USENET still not completely useless regardless of how many outlook readers are out there. If tin isn't your style slrn is my second choice
mutt - while mail is sufficient I like it because of the vi interface
gcc - the entire compiler collection
ssh - if you can

I learned an ingenious trick from the trolls this weekend here on Slashdot. Of particular interest is Serojin. I really do not know if I should be amazed at his creativity to abuse the /. moderation system or at the daftness of moderators to give this person up mods so that a signature line can be changed later to a rather "colorful" link as described by this shock-site informatio