Later that day, Gates gave a speech about privacy on the 100th anniversary of author George Orwell's birth.

In between, he talked with USA Today editors and technology reporters Kevin Maney and Byron Acohido about Microsoft's challenges, his work with the Bill and Melinda Gates Foundation, and his future. Here is an edited transcript:

Question: Do you get spam?

Answer: Oh, yeah. I get more spam than anyone I know. I don't know how much the president gets, but, yes.

Q: How big is the threat to the industry?

A: The increase in reliance on e-mail isn't as great as it would be otherwise. We're not seeing people backing away from e-mail. It's just that the inexorable move to digital communication has slowed down.

Q: What do you spend your time on at Microsoft?

A: Well, my role is the product strategy, so things like speech, handwriting, making work flow more efficient and making sure that as you do these things more effectively, digitally, that you have better security than the equivalent nondigital processes.

I don't know if you've seen the tablet PC. The idea is that you'll be using a pen and you'll be using speech as a natural way of interacting with these devices. That will take place finally this decade — we call this the digital decade, and it's where you get the devices of all sizes working together. Taking the research breakthroughs that we've made and getting those into products is the thing I spend most of my time on.

Q: Microsoft has done great with PC software, but many things that it has tried over the past 10 years to go in different directions have not been hits.

A: Well, let's take a look. Expedia. We sold that for a billion dollars. It cost us $70 million to create. We sold it for a billion. Of dot-com startups, is that a terrible record relative to others? I don't know.

CarPoint makes money. It doesn't make a huge amount of money, but it's a very good business for us. Tablets will be a half-million units this year.

Q: How long can you keep making upgrades of your desktop products?

A: Well, until we have perfect desktop products that nobody can say, "I can't imagine my work flow being more secure. I can't imagine better business intelligence." We see 15 to 20 years of pretty clear milestones that we can drive into those things.

Q: Longhorn — that's Microsoft's code name for the follow-up operating system to Windows XP. What will that do?

A: Say you have two PCs. It's a huge pain that your favorite (Web sites) on this machine are different on this machine. Moving your files from this machine to this machine, getting your e-mail, your calendar — it's painful. So Longhorn makes it easy for your information to show up on any device. Say you keep lists. Anytime that you've mentioned a restaurant, it automatically goes on to this list of restaurants and your system would automatically keep track of the hours, the menu. If you've mentioned a stock, it just goes on this list. It will keep track of the price.

So Longhorn is a change of the user interface to unify a lot of things that have been disparate. But it's a huge project. It's a very ambitious piece of work.

Q: How far down the road?

A: Years. At this time, we're doing the prototyping, feasibility studies, performance studies.

Q: There seems to be some worry at Microsoft about Linux (a rival operating system) and Web-based offerings like SimDesk. Houston, Munich and Beijing have looked at Microsoft alternatives. Is this a big concern?

A: Well, those are our current competitors. I mean, it's no different from in the past when people used (IBM's operating system) OS/2.

Q: Nobody used OS/2 ...

A: Are you kidding? I mean, let's be serious. That was IBM, a company 15 times our size. Name a bank that didn't use OS/2. People always think today's competition is somehow different and unique in some way. Let's be serious. I mean, we've had to bet the company many times on big technological advances. Now we're in the process of betting on a combination of technologies called .Net, which Longhorn Web Services go along with. Who has the guts and the willingness to do risk-taking? Who else is going to push that forward? We've chosen to do that.

Q: Do you run the risk of riding the desktop-centric horse too long, just as IBM rode the mainframe horse too long in the early 1990s?

A: We're doing anything where software runs. On TV, watches, video games, you name it. If it's about writing great software that can empower people, we're doing software for every one of those things. So we're not just betting on the desktop.

Q: Business investment has been one of the lagging factors in the economy. Do you see a turnaround in that?

A: Capital spending on IT (information technology) gear is unlikely to ever, in my lifetime, achieve the levels of the late-1990s. Anybody who's got a business plan where they're holding their breath until those days return is likely to die of asphyxiation.

Q: Does that spell the end of the productivity boom that's been fueling the economy?

A: Absolutely not. That's one thing to be clear about. Our industry in terms of improving its technology is actually doing better work today than any year during the boom.

Remember: Most of the dreams of the bubble never happened.

E-commerce didn't really happen. You have this illusory thing where the simple part of the transaction goes digitally. But if you look at all the faxes and phone calls (workers need to do to) straighten out this pure digital channel — e-commerce is really something that is in front of us in terms of getting the benefits out of it.

Q: Would you talk a little bit about your upcoming Africa trip for the Gates Foundation — what programs and where you'll visit?

A: I'll start in Mozambique. That's about children's vaccination. The new vaccines that, of course, we take for granted here.

Then I go to South Africa, where we do a lot of our AIDS prevention work. Then I go up to Botswana ... that's a combined AIDS treatment and prevention. That's a partnership with Merck where we put, now, $100 million.

Q: A lot of people talk about making a lot of money in their lives, but the most rewarding thing was to give it away. Is that the most satisfying part of your life?

A: Well, the most satisfying part of my life is having kids, playing with my kids, things like that.