Doug Herzog, president of Comedy Central and Spike TV, didn't have his epiphany about the future of television at work. He experienced it on a recent vacation.

Herzog knows the explosive growth of DVR (digital video recorder) technology, which allows viewers to record dozens of shows for later viewing, means that the era of "sitting down at 8 p.m. on a Thursday to watch a particular show because some network tells you to is over."

But getting a firsthand glimpse into the true potential of the tube -- watching what you want, anytime, anywhere, via any number of electronic devices -- was a revelatory experience.

Before he left on a recent trip, Herzog, an avid Yankees fan, signed up with Major League Baseball's MLB.TV, which enables subscribers to watch certain baseball games from anywhere, via broadband computer connections.

Down in Costa Rica, as his family relaxed at a remote resort, Herzog watched American baseball to his heart's content.

"That changed the game for me," Herzog says. "Now I get it."

And Herzog hasn't even seen what subscribers to SkyTV in Britain can do: They can change the camera angles on the soccer games they're watching, and place a bet while they're at it. And they can dump the game's official announcers in favor of commentary from rabid fans.

And though Herzog's sons were watching a "Spider-Man" flick on their portable gaming device on the plane to Costa Rica, a couple of years from now, they might be watching "Chappelle's Show" or "South Park" on their phones.

More than one media pundit has opined that TV is going to change more in the next five years than it has in the last 50. But how does this affect you?

Here, we take at look how television will look in the future: how DVRs and video-on-demand will allow you to access your favorite shows when you want them, how cutting-edge technology will allow you to take TV with you wherever you go, how the Internet may one day become television's secondary (or primary) home, and how advertising will change in this brave, new TV world.

1. Running your own network -- wherever you are.

"Timeshifting" was the hip term among media executives for the past couple of years. It referred to consumers' ability to watch TV and consume other media at their own pace, thanks to DVRs, which let viewers pause live TV, fast forward through commercials and record dozens of shows for later viewing. The rise of DVR technology, which is now available to many cable subscribers, means TV watchers can tune into the nightly news at 1 a.m. or turn on a cooking show at the dinner hour, not when it aired in midafternoon.

There's no doubt that the aggressive rollout of DVR technology by cable firms -- DVRs are also available as stand-alone devices and through satellite TV providers -- has helped ignite the timeshifting revolution. DVRs will be in 25 million homes by 2007, according to the research firm the Yankee Group; Forrester Research estimates that 41 percent of homes will have DVRs by 2010.

But timeshifting is making way for a new buzz term, "placeshifting." Media execs realize that TV audiences don't necessarily want to be parked in front of the TV on their couches. If you can e-mail your friends from an airplane and watch movies while hurtling down the highway in your car, why shouldn't you be able to watch "Law & Order" on your computer, your hand-held gaming device or your phone?

A few months ago, DVR pioneer TiVo made TiVo-to-Go available on the firm's Web site. TiVo-to-Go is a computer program that allows subscribers to download TV shows they've recorded on certain TiVo devices to their computers.

"The response has been phenomenal," TiVo CEO Mike Ramsay says. "Clearly mobility is really important. What we're looking at is a lifestyle. It's about consuming media on the go."

Media companies are working on ways to get TV into your cars -- and not via discs that you pop into a mobile DVD player. Satellite radio firms, for example, are exploring ways to get TV programming into the cars of their 5 million customers. And next fall, consumers will be able to get satellite TV from DirecTV as an option on the Cadillac Escalade. A recent report by the consulting firm Frost and Sullivan predicted by 2011, 3 million cars will have satellite TV -- and 36 million cars will have some kind of video capability.

At least five major cellular services provide some sort of television content on their phones, according to Jimmy Schaeffler, chairman and senior research analyst at the Carmel Group, an independent media research firm.

And these days, what they're offering is more than just "mobisodes," or specially created mini-episodes, of shows such as "24" and "The Simple Life." In April, Sprint began offering real-time feeds of the Fox News Channel to its subscribers as part of its multimedia Sprint TV service, and Verizon's new V Cast service, which costs $15 extra per month, enables cell phone users to watch music videos, "Daily Show" excerpts and "Sesame Street" clips, play games and also get news feeds.