Megan Mullally

While she was a student at Northwestern University, Megan Mullally received kudos for her work in campus musicals, so she dropped out of school to pursue acting.

One of her earliest screen roles was playing a call girl in Tom Cruise's break-out film, "Risky Business," in 1983. She made her debut on Broadway in 1994, playing Marty in "Grease" with Rosie O'Donnell.

Other guest starring gigs on TV would follow, including roles on "Seinfeld," "Frasier," "Mad About You," and "Just Shoot Me." Her break-out role came when she starred as squeaky-voiced Karen Walker on "Will & Grace," beginning in 1998. The show's series finale was in May 2006.

She'll try her hand at hosting daytime TV when her self-titled talk-show debuts in September.