That special something: You have it or you don't. The French call it "je ne sais quoi." It's hard to define, but easy to identify. A lucky few have it. The rest of us can only recognize -- and covet -- it.

The same is true for companies. In the world of information technology, the "it" company (pun intended) is Apple (Nasdaq: AAPL). Beyond its wildly popular iPods, iPhones, and iPads, the company's cachet extends to personal computers.

Most PCs may be old news, but the realm of make-your-friends-and-coworkers-envious, ultraportable notebooks remains hot. Apple redefined that slice of the market with its MacBook Air. Dell (Nasdaq: DELL) tried to compete with its Adamo line, which was discontinued in February after a series of pricing and feature missteps. Hewlett-Packard (NYSE: HPQ) tried to compete with its aptly named Envy 13. Introduced in September 2009 in response to the MacBook Air, the Envy 13 -- like Dell's Adamo -- suffered from too-high pricing and not-quite-right features.

That ain't it, man, that ain't it
There was much to like about HP's Envy 13, including battery life, graphics performance, and a high-resolution screen option. But the standard hard disk drive in the base model missed the mark. Upgrading to a faster, smaller, and lighter solid-state drive bumped the price up by $200. And like Dell, HP made the mistake of pricing its offering above Apple's. What were they thinking? Apple is known for its ability to command premium prices.

After aggressively dropping the price of the Envy 13 in recent months, HP discontinued it in February. According to HP, the Envy 14 is replacing it. But the Envy 14 is no MacBook Air competitor. In contrast to the MacBook Air, the Envy 14 comes standard with a hard drive instead of a solid-state drive. It is also bulked up with an optical drive. Compared to the Envy 13, it's about 50% heavier and 45% thicker … so, not exactly ultraportable.

Foolish takeaway
HP's PC advertising improved markedly after it hired a former Apple marketing executive in 2005. But when it comes to distinctive products, Dell and HP miss the mark. In the meantime, Apple is taking market share in desktops and portables and redefining products such as MP3 players, smartphones, and tablets with its iPod, iPhone, and iPad. In the wake of all these successes, Apple's stunning growth and premium valuation indubitably reflect its ineffable air of je ne sais quoi.