I'm hungry for shares of soon-to-be-liberated eBay (NASDAQ:EBAY) unit Skype.

My motivations are equal parts business and personal. On weekends, I attach a video camera to my Mac and call my parents in California. They're thrilled to see their fast-growing grandchildren on camera. I know the feeling; I got to see my equally fast-growing nephew via a Skype video call from my sister a few days ago. Skype has become the connective tissue with which I keep tabs on family and friends.

But Skype is also an important business tool for me, a freelancing Fool who works far from HQ. Skype keeps a lid on my telephony costs and improves service by substituting for AT&T's (NYSE:T) shaky wireless service in my area.

Mine is a special case, of course. But Skype's growth is unmistakable. Revenue soared 44% to $551 million in 2008. That same year, Skype registered 129 million new users, up 47% year over year.

And growth shows no signs of slowing. Skype had added 75.2 million registered users through June 30, on pace for 150.2 million new users and 555.7 million overall by the end of 2009. Here are two reasons to expect further gains, and one really good reason to buy when Skype becomes an independent public company.

1. The rise of the work-anywhere worker
A global workforce is becoming more distributed by the day, which means more telecommuting. Recently, Cisco said it had generated $277 million in savings by letting some employees telecommute from home.

To be clear, Cisco has an agenda. The networking equipment maker is hawking IP telephony equipment and services to large clients -- making it a corporate Skype, you might say. The company's timing couldn't be better. As recently as 2007, 12 million Americans worked at home at least eight hours per week. Researcher Gartner Dataquest predicted that number would grow to 14 million this year.

The federal government could help to boost those numbers. Roughly 95,000 government employees were telecommuting in 2007, The Detroit Free Press reports. The best tool for these workers? The Web, naturally. 

And they'll get more and better tools if President Obama has his way. The president has earmarked $7.2 billion to increase broadband Internet access across the nation, a likely boon to wireless operators such as Clearwire (NASDAQ:CLWR) and rural-area carriers such as Windstream (NYSE:WIN). More broadband also equals more opportunity for Skype.

2. Traditional networks aren't improving fast enough
Efforts to expand and stabilize Web access have left traditional landline operators such as AT&T, Verizon (NYSE:VZ), and Sprint Nextel (NYSE:S) with little choice but to expand their own offerings. Ma Bell, in particular, has committed $18 billion to network upgrades in 2009, a spokesperson told me recently.

But that hasn't silenced critics. Users otherwise enthusiastic about Palm's (NASDAQ:PALM) Pre smartphone expressed hesitations about switching to Sprint Nextel from their existing carriers. AT&T took a beating on Twitter for failing to disclose its network's problems with visual voicemail delivery.

Such criticism, while fair, can be overdone. Furthermore, the Web and VoIP services such as Skype are no panacea. Think about how many times you've suffered a Web outage. In February, millions of Gmail users lost access when the service went offline for more than two hours.

Yet users remain undeterred. Cloud computing services such as Gmail will account for $56 billion in revenue this year, up 21% from $46 billion in 2008, Gartner predicts.

3. Numbers that are worth buying
Skype has become one of the cloud's most popular services. Brian Krebs, digital security reporter for The Washington Post, said in a recent blog post that he has been "a loyal Skype user for several years now," and that he has his own Skype phone number with custom voicemail.

He's a paying customer like me, in other words. My tab is just $8 a month. Krebs may or not pay more. But we know from the latest data that Skype has generated $611.9 million in revenue over the trailing 12 months, from an average of 409.4 million registered users.

Doing the math shows that Skype is taking in $1.49 per user, per year. If that ratio holds, and Skype's user base grows to 556 million, as expected? Revenue would improve to $828.4 million.

Uh-oh, here comes the math
I'm fascinated by the assumptions cooked into Skype's presumed valuation: roughly $2 billion, according to press reports. Let's project a little. Assuming $828.4 million in 2009 revenue and a 21% operating margin -- in line with the recent past -- Skype could generate $173.9 million in full-year pre-tax profit. Taxing that at 40% leaves $104.4 million. Dividing that by $2 billion equals 19.2.

Skype, at a $2 billion IPO, would sell for close to 20 times 2009 earnings -- perfectly fair for a company with a known brand, a large and loyal user base, and excellent growth prospects.

But that's my take. Do you agree? Disagree? Use the comments box below to tell us whether you would buy Skype if given the chance.

Get your clicks with related Foolishness:

Start investing today – just $7 per trade with Scottrade. Or find the broker that’s right for you.