Whoever came up with the playlist idea, kudos. This gives me a reason to compile a list, which is only to get less complete as time goes on. My mushing days started back in 1995/96? and lasted until mid-2013, with acouple of long breaks in there. The list below is roughly chronological (at least, the WoD part), as much as a I recall...
Cajun Nights: Chantal (mortal), Saralee (mortal), Hadrian (Ventrue)
Metro: Janice (Ravnos), Hadrian (after he left Cajun Nights)
Tempest: AJ (BSD, I think?)
Santo Domini: Isabelle (Tremere), Sachavelli (Giovanni don), Quickstrike (BSD)
Due Rewards: Arkady (Brujah), Liane (M+ CSI), some others I can't remember
Denver Dark Destiny: Isabelle (ported from Santo Domini), Marianne Beaufort (the ridiculously verbose Ventrue), Victor (Gangrel)
Generation X (That 80's Seattle one): Scissors (Bonegnawer Ahroun)
Shadowed Isles: Seanna (Fianna), Rain (Hakken), Aunt Ana (Troll)
Metro v2: Lillian Hayes (Technocracy intern)
Masquerade: Sasha (Corax)
Arctic Rage: Victor (Get of Fenris)
Darkwater: Sydney Rae (mortal, federal agent), Mr. Quiet (Ogre)
City of Hope: Sjovold (Get of Fenris)
Oathcircle: Elisha/Nibbles (Pooka), Mad Jack (Redcap), Megan (Children of Gaia)
The Reach: Marie (Wolfblooded Cop), Poison/Aunt Sigi (Crone/Kross), Oscar/Electro/Sparky (Free Council Obrimos), a couple of others I never got around to play much.
From the Ashes : Ivy (Redcap)
Bump in the Night: Anthony, Olivia.
Fate's Harvest: Svetlana
Birds of War: Mlle. Solace, The Contessa, Jurgen Schlag
Steel and Stone: Alise, Rutger Nayland (the first one, anyway)
Sweetwater Crossing: Lucy Vancamp, Andrew Cash, Elena Avery
Cold Space: Illyanna Shevchenko
The Triangle: Lena Valk
Lantern Hill: Troy, Sophie, Eve
Kushiel's Debut: (briefly) Regine, Vallis, Marilene
Coral Springs: Koa, Bam-Bam
8th Sea: Beppe, Mako
Arx: Veronica Keaton, Vercyn Halfshav
Calaveras: Nina, Eve, Franklin
Savage Skies: Ling, Jericho
Welcome to the Euphoria: Tannen, Jessica
A bunch of others I was on briefly, but just can't remember enough details to list (Memoirs of Betrayal, Fallen Leaves, Hint of Malice, Mountain Cauldron, some others). I had a string of different Black Fury characters but I can't recall any of the games they were on. There was also a handful of comic book MUs that I was on for about 6 months (it was a phase), but I can't recall their names.
Did some sporadic staffing over the years, on Due Rewards (can't remember the staff name) and Tempest (sorry Gany, I was Ms. Orange, unless you took up the mantle later on). Never wanted to staff ever since.