Emacs http://www.gnu.org/software/emacs/
vi, vim, gvim http://www.vim.org/
Crimson Editor http://www.crimsoneditor.com/
Notepad++ http://notepad-plus.sourceforge.net/
Textpad http://www.textpad.com/
Multi-Edit http://www.multiedit.com/
Komodo of ActiveState http://www.activestate.com/
Eclipse http://www.eclipse.org/
SlickEdit http://www.slickedit.com/