This article has been adapted from our sister site across the pond, Fool U.K.

Back in the '90s, I witnessed Steve Jobs addressing the Apple (Nasdaq: AAPL) faithful at a developers' conference, and to say he had the ability to hold the crowd spellbound would be, well, accurate.

Employing what had become known as his "reality distortion field," Jobs had the ability to convince people that all his ideas were great, and that things were going to turn out exactly as he said they would.

And 15 years on from his return to head up Apple and rescue it from its disastrous interlude under the leadership of John Sculley and Gil Amelio, we can see that reality has, in fact, bowed its head to the inevitable and done Steve's bidding.

A share tip
Another thing I remember from those exciting days, as well as a visit to Apple's famous HQ at 1 Infinite Loop, was getting a tip from an Apple tech guy -- not a technical tip, but a "Buy Apple stock" tip. He reckoned Apple had a great decade ahead of it, and how right he was -- the shares were around $5 back then, and they're more than $300 apiece now.

Naturally, I didn't follow his tip -- in the intervening years, I've carried on buying and using Apple computers, but I didn't buy the shares. Oh, well.

Anyway, with the shares having trounced the Nasdaq and soundly beaten just about any technological or investment benchmark you care to mention, am I really suggesting that they're still cheap?

Yep, I am.

Growing sales and profits
In the year to September 2010, Apple turned over $65 billion, which was 50% up on 2009's turnover of $43 billion, and that, in turn, was a third higher than the previous year's $32 billion. And unlike some competitors whose margins are quite thin, from that $65 billion, Apple took $27 billion in gross profit and a pretax profit of $18.5 billion.

How does Apple keep its margins high? Well, most Apple users will tell you it's done by making the best products, for which people will pay a premium. In fact, I'm typing these words on my MacBook Pro, which cost me more than twice the price of a PC laptop of similar specs. When I came to buy it, the thought of not buying a Mac just didn't enter my head, because I want my computers to just work, easily, sensibly, and reliably.

Will profits keep rising? Well, Apple's iPhones and iPads seem to be selling about as fast as they can make them, and Apple faces none of the problems that are confounding competitors such as Research In Motion and Nokia at the moment.

Future products
Apple's early lead in the iPad and iPhone market is being eroded by the advance of machines powered by Google's Android operating system, and I think those are likely to be the two main contenders in the market for some time to come.

Apple's latest venture, iCloud, promises to join everything up properly, in a way that nobody else really can just yet. Take a photo while you're out using your iPhone, and magically it's already there on your Mac when you get home. Want to play some music while you're out? Whatever is on your Mac is also on your iPad or your iPhone, with no messing around deciding in advance what you want to take with you to listen.

It already works well for email, addresses, calendars, and bookmarks -- I have three Macs and they sync those things just fine using online magic. And now iCloud should take that a step further and do the same for photos and music. With Apple's huge investment in server farms to support it, I can't see iCloud disappointing the punters.

What about the price?
The share valuation? Well, here's where it really gets interesting.

Looking back at 2010 again, Apple brought in earnings of $15 per share -- on today's share price, that's a P/E of 21. But for the year to September 2011 (which is only one quarter away now), EPS of $25 is forecast, putting the shares on a trailing-12-month P/E of 15.6. And that falls to just 12.5 for the full year.

And if we look at the current estimates for 2012 of $29 per share, that's a prospective P/E of under 11 -- and that's cheaper than U.K.-based supermarket giant Tesco!

The big question
Of course, there's one question I haven't asked yet, and it's a biggie -- what will Apple be like without Steve Jobs?

He won't be the boss forever, and after his well-publicized bout with pancreatic cancer back in 2004, and his recurring health scares since, many are expecting him to step down sooner rather than later -- in fact, Steve took a medical leave of absence only this year, in January, just a year and a half after his successful liver transplant in 2009.

How long will he remain at the helm? Will he be able to loosen his "hands-on" approach to running the company? Is there a succession plan in place? All these questions and more will be answered, erm, sometime.

I reckon Apple is well enough developed, with a corporate culture that infuses it from top to bottom, and has some of the best techies and managers in the business -- and it will avoid floundering when it comes to the post-Jobs era.

The shares will probably take a bath when Steve steps down, though, even if it's only due to sentiment. But how high will they get before that day, and where will they go afterwards?

Those are questions we can't answer right now -- but we're still looking at possibly the world's best technology company, with its shares on a supermarket rating.

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