"I find the function of the brain incredibly fascinating, and it's like trying to crack the toughest, most complicated problem there is," Allen said.
In the years since he left Microsoft, Allen has pursued several passions, including music, sports, philanthropy and travel. Allen is the founder of the Experience Music Project in Seattle, which contains the world's largest collection of memorabilia devoted to Jimi Hendrix.
Allen is a hard-core music aficionado, and he keeps several guitars in his office, including his prized Martin Robbie Robertson acoustic, which he described as a "fantastic guitar."
In an interesting historical anecdote, Seattle-born Allen said he applied to Reed College in Portland, Oregon, in 1972 and was accepted, but did not attend because his parents could not afford the tuition. Instead, Allen went to Washington State University, but dropped out after two years to move to Boston, where his childhood friend Gates was attending Harvard.
Apple co-founder Steve Jobs attended Reed in 1972, so it's interesting to think about what might have happened if Jobs and Allen had met in Southeast Portland. (Disclosure: I went to Reed.)
Allen has done much to boost the economy of his beloved Pacific Northwest. He owns the Portland Trail Blazers basketball team, and the Seattle Seahawks football team.
In 2008, the Seattle-King County Association of Realtors honored Allen for his "unwavering commitment to nonprofit organizations in the Pacific Northwest and lifetime giving approaching $1 billion." That same year, Allen was awarded the Herbie Hancock Humanitarian Award from the Thelonius Monk Institute of Jazz for "his visionary achievements as a businessman and a global philanthropist."
In our Wired.com interview, Allen stressed the need for people to find a balance between work and other pursuits.
"In the first eight or so years at Microsoft, we were always chained to our terminals, and after I got sick the first time, I decided that I was going to be more adventurous and explore more of the world," Allen said.
"Technology is notorious for engrossing people so much that they don't always focus on balance and enjoy life at the same time. So I think it's important to complement, as we used to say at Microsoft, the 'hard-core' investment you're making in your work with some adventure and some real enjoyment of life at the same time."