I know I am missing some, I hope someone sees this and fills in.
Keep in mind, some of these have specific dates on them, but I don't know if they pop back up when the holiday comes back around... such as #s 155, 156, 157... has anyone obtained those since 2006?
Well, combining your list with the one I made on the official forums...
The list of time limited/rare badges:
* Celebrant (year 1 badge May 2005), Reveler (year 2 badge May - June 2006) having both gave a 5th columist gladiator, Merrymaker (2007), Entertainer (2008). Login badges.
* Pursuer(CoH)/Elusive(CoV). November 2006. Login badge.
* Frozen Fury: Winter Lords. Winter 2004 event, repeated for Winter 2006.
* Cold Warrior: Winter Hordelings. Winter 2004, 2005, 2006 events.
* Hallow Spirit, Hunter, Buster, Shifter, Dead Head, Malleus: The Halloween event 2004 & 2006, 2007.
* Iron Warrior, Ghost Touched: Halloween event 2006, 2007.
* Clothes Horse, Fashionable, Ostentatious: Halloween event 2007. Costume powers collection.
* Heart of Light(CoH)/Heart of Darkness(CoV): Valentines 2006 Event. Gave Toga costume option. Login badge. Mission complete in later years (2007, 2008), some people still have access to mission, but fairly rare at this point.
* Hellfrost gladiator(CoH), Hordeling Lasher gladiator(CoH), Coldblooded(CoH), Weed Whacker(CoH), Beautiful / Handsome: Valentines 2006, 2007, 2008
* Partygoer Valentines 2007, 2008 mission complete badge.
* Toothbreaker (Gives rad cap gladiator), Cap Buster(CoV): Valentines 2006, 2007, 2008, Winter 2006, 2007 events.
* Toy Collector (gives Snowbeast gladiator), Longbow Reservist(CoH)/Jetsetter(CoV), Holiday Spirit(CoH)/Scrooge(CoV) were all winter 2005 event. Toy Collector repeated for Winter 2006, 2007 events.
* Cold Front, Trucker: Winter 2006. Login badge. (Could buy with candy canes in 2007 event).
* Joyful, Miraculous, Frosty, Crystallized, Bane of Dannon(CoV): Winter 2006, 2007 events.
* Speed Demon, Accelerated, Qualified Winter 2007 Ski run badges.
* Gifted: Winter event 2007.
* Passport: (North American to EU Transfer badge, no longer available)
* Power Liberator / Master Thief: (not obtainable until Items of Power are returned to the game.)
* Bug Hunter: (Yeah, I know it is technically available, but there is absolutely nothing a character can do to obtain it, granted solely on the discretion of the developers.)
Oh, and:
I believe the Event Badges are perminent, the Text changes per year (if any specific timeline is mentioned) but the Badges themselves are the same.
This is incorrect. The texts do not change.