Sophia Bush & Dave Navarro
Brooke's bachelorette party includes a wild ride with the Jane's Addiction frontman.
David Arquette
Despite his messed-up marriage and possible addiction troubles, David Arquette found time to guest star on his sister Patricia Arquette's series Medium before that long-running show's series finale, scheduled for Jan. 21.
Joe Jonas
The cutest JoBro and our own Jason Kennedy guested in an episode of 90210 that showcased Adrianna's (Jessica Lowndes) increasing celebrity.
Gwyneth Paltrow
Mr. Schu finds a good reason not to use his own umbrella-ella-ella when the Academy Award-winning actress shares the stage on Glee.
Michael J. Fox
The five-time Emmy winner returns to the small screen as a disabled attorney taking on Alicia (Julianna Margulies) and a major pharmaceutical company in the Nov. 9 episode of CBS' The Good Wife.
Mark-Paul Gosselaar
The former NYPD Blue star (Oh, who are we kidding?) Zack Morris stopped by Weeds for a one-night stand with Nancy Botwin (Mary-Louise Parker).
Britney Spears
The "Britney/Brittany" installment of Glee was stunt-casting magic, and Britney Spears' visit to McKinley officially became a creative and financial triumph for Fox's hit musical dramedy.
Matt Damon
Tina Fey has scored another award-winning actor to play her boyfriend on 30 Rock. How will Liz Lemon spoil this one?
Jennifer Lopez
J.Lo guests on the March 8 ep of How I Met Your Mother as "Anita, a self-help author, who tries to lure Barney (Neil Patrick Harris) into falling head-over-heels for her."
Sheryl Crow
The singer guests on Cougar Town as a love interest for Josh Hopkins who also finds time to canoodle with Brian Van Holt. Lucky girl!
Kathy Griffin
The world's greatest D-Lister guest stars as a gay activist on Law & Order: Special Victims Unit on March 3.
Snoop Dogg
The rap star appears as himself on One Life to Life on Feb. 24 to perform a remix of the show's theme song.
Carrie Underwood
Neil Patrick Harris tweeted this first look at the country singer on the set of How I Met Your Mother wearing a retro stewardess outfit. NPH captioned the photo "You'll love the way we fly."
Benjamin Bratt
Det. Rey Curtis returns to Law & Order next Friday, Dec. 11, after a 10-year absence, to help solve a case that appears to be about a dead fed.
Zooey Deschanel
It's about darn time! Emily Deschanel's baby sister finally guest stars on Bones on Dec. 10. We are unreasonably excited about this. How 'bout you?
Freddie Prinze Jr.
Mr. Sarah Michelle Gellar joins the cast of 24 this January. We can only assume this is part of a charity outreach effort of some kind.
James Van Der Beek
The former Dawson's Creek star is guesting on ABC's unmemorable The Forgotten on Dec. 1.
James Franco
The Spider-Man bad boy hits the daytime drama, opposite Kirsten Storms, beginning Nov. 20.
Padma Lakshmi
The Top Chef hostess guests as herself opposite Alec Baldwin's Jack Donaghy on the Nov. 12 episode of 30 Rock. Looks like Sheinhardt Wig Company is really bringing the cross-network synergy this season!
Samantha Ronson
When the celebrity DJ guests as herself on the Nov. 3 ep of 90210, she takes a moment to give Navid (Michael Steger) some dating advice. He should take her advice with a grain of salt, though, seeing as how SamRo and LiLo are featured prominently in our Most Dysfunctional Celebrity Couples gallery.
Lady Gaga
A version of the loopy singer appeared this week on Gossip Girl (in the form of a wee Lithuanian trick-or-treater visiting Rufus and Lily's apartment), but the real deal stops by the Nov. 16 episode to perform one of her pop-hit songs and visit with the likes of Penn Badgley and Leighton Meester.
Gavin Rossdale
Mr. Gwen Stefani rocks the eyeliner as a suspected murderer on Criminal Minds on Nov. 11. The best part? The BAU team suspects vampiric influences may be at work. We suspect Twilight influences may be at work.
Gina Torres
The imperious Firefly star comes to Gossip Girl for the rather ridiculous purpose of playing Vanessa's mother as such an unrepentant hippie that she doesn't approve of institutions of higher education or of her daughter (Jessica Szohr) being elected to make the freshman-class speech. Come on!
Summer Glau
Um, whatever happened to Grindhouse Fridays on Fox? We weren't expecting Summer to look so milquetoast when she guest-stars on Dollhouse.