2. Marissa Mayer, Google

Mayer was the first female engineer hired at and one of its first 20 employees. Since then she's gone on to become vice president of location and local services for the company, but other accomplishments there have included designing and developing Google's search interface and internationalizing the site to more than 100 languages.

"I love technology, and I don't think it's something that should divide along gender lines," Mayer told Newsweek in an last year. "One of the things I care a lot about is helping to remove that stigma, to show girls that you can be feminine, you can like the things that girls like, but you can also be really good at technology."

3. Carol Bartz, Yahoo

As CEO of Yahoo, Carol Bartz is nothing if not a visible IT leader. With a career including stints at Autodesk and Sun Microsystems, Bartz has been an outspoken advocate of women in leadership roles. "Most people assume that because I'm a woman, I'm someone who's standing behind a leader, a man," she's been quoted as . "The fact that they're unenlightened is their problem, not mine."