ITT: You describe your relationships with people you think are your identity, mirror, dual, conflict or what have you. I'll start.
Identical: I only know three EIEs so far: Gilly, my own mother, and (I suspect) a fairly hot female friend of mine. I have an awesome relationship with my mom, Gilly I got along with pretty well (although I'm feeling ambivalent towards him; he was a real asshat to a very close friend of mine who also posts here). Me and said friend have a good relationship; though pretty heavy on the flirting on both ends. Nothing's happened yet, but I'm fairly certain it will at some point.
Mirror: My best friend is an IEI (to be precise, he is my exact mirror -- he's an Fe-IEI-ILE, to my Ni-EIE-LII). We have the same interests, and mostly the same off-kilter and non-mainstream political viewpoints, and overal we get along awesomely. I think my high school sweetheart was another IEI.
Kindred: A friend I have from an MBTI (Typology Central) forum is, I believe, ESE. She and I get into minor scuffles all the time, usually over issues of stereotyping (Democratic/Aristocratic rift -- Type Central is annoyingly Democratic, and "stereotyping" is a big deal there), but our shared Fe usually defuses the situation within minutes. Neither of us can really take ourselves seriously. Another of my best friends is also probably my kindred (I think he's ESE-LII). We get along great, although he has an obsession with sports and women that I don't share.
In general Puerto Rican culture is very ESE, and the rampant Si kind of annoys me. I can't find anything in common to talk about with most people, which bugs me (which is why I spend most of my time attention-whoring online).
Activation: Another guy I know from Type Central is SLE. He's one of the few people that appreciate my blunt directness and haughty demeanor in debates (Se Mobilizing coming out there. Forum discussions are just about the only place where I don't pull any punches).
Semi-dual: Hot nerdy friend of mine is LII; a bit older than me. As with my kindred above we have a bit of a Democrat/Aristocrat rift going on (she bitches about stereotypes sometimes, I pretend to go along with it); but otherwise we get along great. She loves my theatrics.
Supervisor: My late grandmother (RIP) was SEI, as is my aunt and a good friend of mine. This chick I had a crush on once was probably SEI as well -- and predictably enough, she had the ability to make me do whatever her little heart desired. Unfortunately she had a boyfriend, so nothing ever came of it.
Beneficiary: I have an SEE friend. She's pretty hot, and she's into me, but I'm keeping my distance because I know nothing good can come of it. She'd likely be a bitchy housewife type, and I don't really like those.
Extinguishment: I know several EIIs from various forums, and pretty much all of them annoy the living shit out of me. Bunch of whiny PC bitches (they usually don't know it though, because I tend to put on an Fi smokescreen when dealing with them -- I guess I just gave myself away, ah well).
And, that's about all I can think of. Anyone got more?