Some brands may be incredibly high-profile, with a nearly universal recognition factor, yet still never stray very far from their niche. Starbucks is all about coffee drinks, McDonald's is where you get a burger and fries, and Budweiser is the King of Beers. And that's pretty much the end of those branding  stories.
Or close to the end. Those brands do attempt some diversity. Starbucks sells exclusive music CDs, McDonald's has attempted to be Starbucks with their in-store McCafes, and Budweiser T-shirts are on sale at Old Navy--but these are mostly merchandising gimmicks or attempts at brand extensions with their current categories. There's nothing revolutionary going on.
Then there are the über-brands like Virgin. Forty years ago, Richard Branson chose the whimsical name for a record store, because he and his employees were relatively new at business. Since that humble beginning, the Virgin name has been applied to an incredible array of products and services : beverages, airlines, trains, video games, financial services, films, cable TV, books, cosmetics, jewelry...well, it might take less time to list the ones that Virgin isn't involved with in 2012.
Then there's Google, which started out as a one-trick pony, by creating the best search engine available at the time. Since that time, it's created office applications, a social networking site, the Android mobile phone OS, the Chrome web browser...and a driverless car! 
Disney also saw past its Mickey Mouse beginnings to becoming a huge entertainment conglomerate encompassing movie studios, television networks, theme parks and even specialty cruises with the Disney brand, while Apple leapt from premium computers to dominating the music industry with iPods and iTunes.
So...why do some brands easily transcend their initial product category, while other ones that were just as powerful at the time, fail miserably? 
The main reason is that Google, Virgin, Apple and Disney, among a few select others, aren't just selling a product--they're selling a promise. They represent something special beyond whatever they sell, a set of perceived intangibles which are more powerful than any individual ad slogan or campaign.
Here are four elements that are critical to creating a transcendent brand:
All four of the brands discussed above initially positioned themselves as innovators and creators of something that hadn't been seen before. Disney brought to life the first "talkie" cartoon, the first animated feature and the first super-sized theme park. Apple and Google, of course, developed breakthrough technology, and Virgin founder Richard Branson built his brand off his image as a brash adventurer who approached business with an irreverent and daring energy that hadn't been seen before.
When you think of Disney, you think of the entire family enjoying entertainment together. Apple conjures up images of sophistication and creativity; you always see high-level creative characters in movies using Apple products. Large segments of the population (with big buying power) identify powerfully with brands that reflect their views of themselves; that's why those brands can leap to different product categories with ease.
Google's unofficial motto was "Don't be evil"--and they still revisit the values  with which they began their corporate life and which resonate strongly with their followers. Similarly, the founding figures of Walt Disney, Apple's Steve Jobs and Richard Branson all represent certain core truths that bond them to their customer base in an emotional way that a company like Coca-Cola has to market heavily  to try and approach, which is why Coke has never grown far beyond its beverage roots.
Returning to Coca-Cola, you could make the argument that there really isn't much difference between them and Pepsi. You could make a similar argument about Budweiser and Miller. But who is like Google? Can you conceive of another Disney?
Transcendent brands stand by themselves. They've fulfilled their brand promise on such an epic scale that no one can really steal their thunder on a long-term basis. They rarely make a misstep with their brand extensions--and when they do, they're quick to correct their course.
The real secret of a creating a transcendent brand can be boiled down to one of Apple's most memorable ad campaigns, "Think Different."  When a brand truly thinks different--and that fresh perspective has a profound impact on the public--it grows beyond any specific product or service. It transforms into an idea that consumers are willing to buy in almost any form it takes.
[Image: Flickr user JD Hancock ]