My feeling is that the more obvious UFAI-alike in MoR is Quirrelmort. Consider: Inhumanly fast (newspaper reading; duel with Bahry). Inhumanly intelligent (passim). Very powerful in part because of being inhumanly fast and intelligent. Interested -- supposing him to be Voldemort, on which topic I shall say no more -- in defeating death (just the sort of thing someone might ask a superintelligent AI to find ways to do).
Speaking of which: "Tell them I ate it", says Quirrell concerning the destroyed Dementor. Dementors in MoR are a symbol of death, even if many wizards don't quite grasp that. Dumbledore doesn't, but Harry surely does. Is Quirrell really not concerned that Harry may get the message: "I am a death-eater"?
But does Quirrell know, or suspect, that Dementors are a form of death? If not he wouldn't even notice.
- This thread has run its course. You will find newer threads in the discussion section.
Another discussion thread - the fourth - has reached the (arbitrary?) 500 comments threshold, so it's time for a new thread for Eliezer Yudkowsky's widely-praised Harry Potter fanfic.
Most of the paratext and fan-made resources are listed on Mr. LessWrong's author page. There is also AdeleneDawner's collection of most of the previously-published Author's Notes.
Older threads: one, two, three, four. By tag.
Newer threads are in the Discussion section, starting from Part 6.
Spoiler policy as suggested by Unnamed and approved by Eliezer, me, and at least three other upmodders:
It would also be quite sensible and welcome to continue the practice of declaring at the top of your post which chapters you are about to discuss, especially for newly-published ones, so that people who haven't yet seen them can stop reading in time.