Tim Connors writes:
Emacs can definitely do it, but is not so scriptable in a self contained bash script (hmmm, users might not appreciate me writing an emacs --no-init-file and big elisp bundle just for a small lightweight monitoring display).
As you hinted, M-x follow mode RET & comint, shell, compile or similar, poss. with M-x ansi color for comint mode on RET, which gives color sequences only. If you need stuff like tput cup, M-x ansi-term, but I doubt that works sanely with follow-mode. You can't have follow-mode in emacs -batch. The only other idea I have would be to do something wacky like rendering a long, thin xterm offscreen, then grabbing its top and bottom and displaying them side-by-side, using opengl or something (I skipped that class). I was talking to a guy yesterday who was doing something along those lines so he could have floating xterms embedded in his Oculus Rift 3d space.