I love ed. A long time ago when I was mastering it, I made an ed cheat sheet. Here it is the article about it:

http://www.catonmat.net/blog/ed-unix-text-editor-cheat-sheet...

And here is the cheat sheet itself:

pdf: http://www.catonmat.net/download/ed.text.editor.cheat.sheet....

txt: http://www.catonmat.net/download/ed.unix.text.editor.cheat.s...

doc: http://www.catonmat.net/download/ed.text.editor.cheat.sheet....