The text editor with which the Angels in Heaven code C.
It is
small, fast, and has hundreds of
time-saving features. Best of all, it doesn't ship with an annoying
paper-clip that tries to tell you what to do.
vi has a steep learning curve that keeps MS using morons far away, but there is a Wintel port so that true Geeks can feel at home if the must be on an M$ box.