How I Met Your Mother
Barney's secret past resurfaces when an old colleague (Chris Kattan) comes to town to reminisce about their days in the niche Blaxploitation/James Bond parody film genre in the only Undercover Brother reunion episode you'll see all season, only on CBS!

House
It's the Spice World reunion the world's been waiting for, as Sir Elton John is treated by Dr. House, playing a very sick man who was poisoned by his own glasses in the episode that causes Dr. House to question his own fashion accessories and their bearing on his tumultuous relationship with Cuddy.

Gossip Girl
Gossip Girl is proud to welcome back Taylor Momsen for a three-episode Underdog reunion special as Peter Dinklage guests as the Humphreys' new dog walker with a secret. Will the Humphreys get a dog in time for the arc to be believable? Tune in and see Mondays at 9!

30 Rock
When Cameron Diaz guests as Jack Donaghy's new sister-in-law, it's not enough to just say Cameron Diaz is guest-starring on 30 Rock, it has to be promoted as a My Sister's Keeper reunion event!

Californication/United States of Tara
In an unprecedented Showtime series crossover event/reunion event/product placement event, Hank Moody will use his unique sexual prowess to seduce each and every one of Tara Gregson's personalities at a book-signing event at her local Borders. But when Hank and Tara get caught having a drink at a drag show, it's curtains for their relationship, in the biggest Connie & Carla reunion event in pay cable history!

Grey's Anatomy
Since Grey's Anatomy is already both a Made of Honor reunion (Patrick Dempsey and Kevin McKidd) and a Valentine's Day reunion (Patrick Dempsey and Eric Dane) every week, tune in for the Wedding Planner reunion event on Grey's Anatomy, as Dr. Alex Karev's (Justin Chambers) life is in grave danger after being run over by that dumpster that almost killed J.Lo in that movie, only this time, there's no Matthew McConaughey -- just Seattle Grace's staff of C-list rom-com heartthrobs -- to save his damaged brain... and his crushed heart.

Your ideas? Put 'em out there in the comments. Networks will totally use them.

Find out more about Will Ferrell's Office arc.

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