The internet has become the new operating system with many companies moving many of their operations online. Microsoft Corporation (NYSE: MSFT) holds the monopoly on desktops and had the lead on web browsers until recently when competitor Firefox took a large share of the web browser market. So, how much is Firefox worth and should Google Inc. (NDAQ: GOOG) consider looking at Firefox?

How much does Firefox make? SpreadFirefox.com indicates that 622,003,431 people have downloaded the Firefox web browser with experts estimating that the firm makes $1 per download from the Google search box in the corner. The numbers suggest that the company is making between $100 million and $200 million per year in gross revenues with solid growth rates.

Additional revenues could be easily realized through other browser add-ons, default homepage ads, and other techniques. Since the Mozilla Foundation is more of a non-profit organization, revenue-generating activities have been kept relatively simple and limited in scope. Moreover, changes may alienate some users. Regardless, there is ample opportunity for increases.

Next, expenses must be considered. Mozilla's employee count is estimated at around 90 with more hiring planned in the future. Assuming that the firm has 100 full-time employees at $100,000 per employee, plus $50 million a year in other equipment/service costs, total expenses are around $60 million per year. This pegs the annual gross profits at around $40 million to $140 million.

Public companies also face additional costs that must be included in the net profit calculation. Sarbanes Oxley compliance costs around $5 million a year with taxes taking out an additional chunk of change. This would leave the firm with around $40 to $90 million in net income after all is said and done.

Investors know that public companies all trade at earnings multiples based on growth rates. Given the market growth, investors could expect a minimum price-to-earnings ratio of 25x earnings, which implies a valuation of around $1 billion to $2.2 billion. This is relatively conservative given the recent valuation of Facebook by Microsoft and acquisitions by Google.

Of course, Mozilla has repeatedly insisted that it would not go public. However, growing pressure on Google to find new revenue growth streams may force them to take a look at the company (Microsoft wouldn't have a chance) while the increasing valuations may be too much for some to resist.