Scenes from Microsoft's CEO Summit (photos)

Even though he's no longer a CEO--or even a full-time Microsoft employee--Bill Gates managed to score an invitation to and speaking gig at the company's CEO Summit this week.

Among the other high-profile guests at the Microsoft event were Wal-Mart Chairman Rob Walton, JP Morgan Chase CEO Jamie Dimon, and IAC Chief Executive Barry Diller. The event runs through Thursday at Microsoft headquarters in Redmond, Wash.

Read more in our related article: "Ballmer pitches cloud to fellow CEOs"

Amazon CEO Jeff Bezos often competes with Microsoft, but nonetheless is among those who take part in the company's annual CEO Summit event.

Read more in our related article: "Ballmer pitches cloud to fellow CEOs"

Legendary investor and Gates' friend Warren Buffett was also on hand for the CEO Summit.

Read more in our related article: "Ballmer pitches cloud to fellow CEOs"

Treasury Secretary Tim Geithner is another of the high-ranking people seen at Microsoft's CEO Summit this week.

Read more in our related article: "Ballmer pitches cloud to fellow CEOs"