Hmm, well I do believe we already had a thread like this
here on FF.net, and the casting possibilities eventually came out something like this:
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Kim - Summer Glau, Hayden Panettierre, Katee Stackhoff, Miley Cyrus
Ron - Shia LeBeouf, DJ Qualls
Wade - Corbin Bleu, Kyle Massey
Rufus - CGI, voiced by: David Scully, Nancy Cartwright
Mr. Dr. P. - Gary Cole, Richard Dean Anderson, David Duchovny, Ioan McGrubber
Mrs. Dr. P - Dana Delany, Gillian Anderson, Mariska Magdolina Hargitay, Uma Thurman, Julia Roberts
Nana Possible - Debbie Reynolds
The Tweebs - Cole and Dylan Sprouse
Dr. Drakken - John DiMaggio, Bruce Campbell, Jeremy Irons, Paul Giamatti
Shego - Tricia Helfer, Lexa Doig, Fran Drescher, Claudia Black, Eliza Dushku, Aishwarya Rai, Jordana Brewster, Nicole Sullivan
Monique - Raven, Beyonce, Keke Palmer, Kandyse McClure
Bonnie - Megan Fox, Mila Kunis
Mr. Barkin - Patrick Warburton
Mr. Stoppable - Edward James Olmos, Elliot Gould
Sr. Senior, Sr. - Ricardo Montalban
Sr. Senior, Jr. - Gilbert Gottfried, Dwain "The Rock" Johnson
Josh Mankey - Seth Myers
Dr. Director - Rachel Lutrell, Angelina Jolie, Mariska Magdolina Hargitay
Motor Ed - Hulk Hogan, Kevin Sorbo
Monkey Fist - Adrien Brody
Duff Killigan - Simon Pegg, Mike Myers, Brian George
Martin Smarty - Patrick Stewart, Kevin Spacey
Tara - Hayden Panetierre, Katee Stackhoff, Chelsea Staub
Sensei - Keith Carradine, George Takei
Yori - Lucy Liu, Stephanie Chaves-Jacobsen, Brenda Song, Michelle Yeoh
Dementor - Patton Oswalt
Ned - Eddie Deezen
Shego's Mum - Michelle Forbes
Frugal Lucre - Jim Carrey
Hank Perkins - Jim Carrey
Camile Leon - Ashley Tisdale
Future Ron - Chuck Norris
Future Drakken - Lou Ferrigno
Future Kim - Geena Davis
Future Wade - Samuel L. Jackson
Kim's Ride - Micheal Shanks
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There! There's the complete list of every casting call we could think of. Now, wait for it . . .
"You're insane!"