That calico has been lurking around my place with increasing frequency. What I've found out via a neighbor is that she has an owner, but he is rarely home (neighbor believes he's home every weekend), explaining why Calico Kitty is really hungry every time she comes around here. A couple of days ago, she was so hungry she even let me touch her while she ate! Only the briefest of contact; not really 'petting' in any sense of the word.. but I got to reset my 'time since I last touched a cat' counter, which had made it past the three-month mark.
So that's something. I fed her again today, and also got to briefly touch her. Building up trust and all that.. it's just too bad I won't be here from Monday onwards.. I hope she survives the winter, but there's nothing I can do about it.