Achivements & Reputation

Some day (cue wistful music and sepia tones), I'd like to implement an achievement system, like you find in MMORPGs:

I'm actually quite surprised that there aren't any, as far as I know, roguelikes with an achievement system. Though you could argue that the game score is a measure of achievement in itself.

Further to that, I'd like to implement factions & reputation (with faction quartermasters):

Of course, you could argue that the deities in Crawl are effectively factions.