Gods, fuck. I just spent awhile writing up a list of affilitations, and then I hit the wrong key and killed the window.
Okay, in brief: A random menu of affiliations, including mega-corps like Renraku, Nova, Aztechnology, Lone Star, as well as smaller local players like Federated Boeing, and a generic "Small Corp" listing would be good. But those aren't the only affiliations, you should have a nice chunk for Indepedant (regular fixers, and other Runners,) as well as the big gang players, a single listing for "street gang" and "Go gang", as well as maybe a 5% each for "UCAS Local Government" and "UCAS Federal Government."
Alternatively, you might make a treasure-like list of what each contact can do for the player, and what they would require from them, although most DMs can come up with it based on that affiliations list. A street ganger is unlikely to be able to get you a SIN, while a contact in the UCAS Federal Government would probably have a hard time finding you weapons and safehouses. (At least, safehouses that don't ask questions.

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