There are novelty Twitter feeds, and then there are novelty Twitter feeds—those that are so genius in their simplicity that somehow, magically, the joke hasn't gotten old in ages. ("Ages" in Internet terms being a few days.) And thus we have T-800, a Twitter representation of Arnold Schwarzenegger's character from Terminator, which so far has done one of two things:
1) Tweeting binary.
2) Tweeting @ people who are named Sarah and asking, "Sarah Connor?" (Occasionally mixing it up with, "I'll be back," or "Fuck you, asshole.")
And to answer your next question: Yes, he's tried Sarah Palin, but miraculously, she doesn't seem to be the one who will give birth to the savior of the human race. (Insert joke about one of the Palin kids, as there are many comedically fruitful options.)