The 10 Most Disruptive Technology Combinations

But MP3 files' small size--roughly one-tenth the size of similar-quality .wav files distributed on CDs--was tailor-made for the broadband explosion of the late 1990s. The emergence of Winamp in 1997 made ripping CD tunes into MP3s easy, and the first portable players (the MPman F10 andthe Diamond Rio PMP300) allowed music fans to listen to them without a computer. In 1999, Napster arrived, giving users an easy way to find new MP3s and share them--much to the chagrin of the Recording Industry Association of America.

Even if Napster didn't kill the record industry (my vote goes to the industry's own greed and stupidity), it changed the business irrevocably. Though the original incarnation of Napster wasbrought down by legal battles, it paved the way for peer-to-peer networking to develop as a legitimate distribution medium. If not for Napster, BitTorrent might not exist. Ironically, when Nine Inch Nailsrecently released its Ghosts I-IV album, it used BitTorrent to help distribute the first nine tracks free for the asking.

Disruption: The idea that media should be portable is disruptive. The notion that it should be free--and that some artists can survive, or even thrive, despite a lack of sales revenue--is even more so.

6. Blogs + Google Ads

Not long ago, if you wanted to be a publisher, you had to either be born into a rich family or become an HTML geek. Now, thanks to simple tools such as Blogger, TypePad, and WordPress, anyone can be a publisher or producer, no technical expertise (or talent) required. "Explosive" doesn't even begin to describe the growth of blogs, which surged from about 100,000 in 2002 tomore than 70 million last year, according to Technorati.

The problem? At first, blogging wouldn't pay your bandwidth bills, let alone the rent. Enter Google AdSense: Introduced in 2002, this program makes adding pay-per-click ads to any site a snap. Google's search engine, meanwhile, offers a self-perpetuating marketing vehicle; the more sites that link to your blog, the higher it rises in Google search results, leading to more traffic, more clicks, more links, and so on. The top 50,000 blogspulled in $500 million in ad revenue in 2006 [PDF], according to a study by the University of Texas and blog-ad firm Chitika. Spread across all the sites in the survey, that amount is hardly a vast fortune, but it's a promising start. (Don't quit your day job--yet.) Overall, in 2007 Google shared more than $5 billion in ad revenues with its partner sites, including traditional Web publishers and blogs.

Unfortunately, with disruption comes drawbacks. Roughly one out of four blogs are bot-created spam blogs (or "splogs"), according toWordPress founder Matt Mullenweg. Click fraud generates bogus income for scammers, spyware infects users' PCs in order to drive them toward splogs, and search-engine-optimization consultants try to manipulate Google's PageRank algorithm to their own ends, skewing the results.

Disruption: Blogs give everyone a public voice, while Google gives bloggers a way to fund and market themselves--and the economy of the 21st century is born.

5. Cheap Storage + Portable Memory

When IBM invented the RAMAC hard drive in 1956, it stored5 megabytes of data and cost $50,000. We've come a long way, baby.

In 2005, Toshiba introduced the first 1.8-inch 40GB drive using perpendicular magnetic recording, which stacks magnetic charges on the disk's surface vertically instead of horizontally. Since then, density rates for hard-drive platters have increased 40 percent annually. Last October, Western Digital introduced a perpendicular drive capable ofstoring 520GB per square inch, enabling multiplatter hard drives 3 terabytes in size.

As densities have risen, the costs have dropped tobetween 30 and 40 cents per gigabyte--cheap enough that companies such as Google and Yahoo can give storage away, enabling free Webmail, online photo and video sharing, and other cloud-computing services.