Traveling to space or embarking on an expedition to excavate lost Mayan ruins are normally the stuff of adventure novels. But for employees of Facebook, these and other lavish dreams are moving closer to reality as the world's No. 1 online social network prepares for a blockbuster initial public offering that could create at least a thousand millionaires. The most anticipated stock market debut of 2012 is expected to value Facebook at as much as $100 billion, which would top just about any of Silicon Valley's most celebrated coming-out parties, from Netscape to Google Inc. Facebook employees past and present are already hatching plans on how to spend their anticipated new wealth, even as securities regulations typically prevent employee stock options from being cashed in until after a six-month lock-up period. “There's been discussions of sort of bucket list ideas that people are putting together of things they always wanted to do and now we'll be able to do it,” said one former employee who had joined Facebook in 2005, shortly after it was founded. He is looking into booking a trip to space that would cost $200,000 or more with Virgin Galactic or one of the other companies working on future space tourism. That's chump change when he expects his shares in Facebook to be worth some $50 million. A group of current and former Facebook workers has begun laying the groundwork for an expedition to Mexico that sounds more suited to characters from the Steven Spielberg film “Raiders of the Lost Ark” than to the computer geeks famously portrayed in the movie about Facebook, “The Social Network.” Founded in a Harvard dorm room in 2004 by Mark Zuckerberg and his friends, Facebook has grown into the world's biggest social network with over 800 million members and revenue of $1.6 billion in the first half of 2011. It is clear that Facebook's earliest employees, who were given ownership stakes, and early venture capital investors will see the biggest paydays. But the wealth will trickle down to engineers, salespeople and other staffers who later joined the company, since most employees receive salary plus some kind of equity-based compensation, such as restricted stock units or stock options. There is always the risk that talented staff would leave with their newfound wealth to make their own mark in the technology world by becoming entrepreneurs. Some Facebook employees have already left the company to do that, selling their shares ahead of the IPO on private exchanges such as those run by SecondMarket or SharesPost. One such person is engineer Karel Baloun, who joined the social network in 2005 and left just over a year later to start his own online network for commodities-futures traders. It failed and Baloun laments that he could have made a lot more money if he had stayed at acebook. But he is philosophical, saying that the equity windfall gave him the cushion to do new things. “It's really wonderful being able to choose your work based on the meaning of it, not the size of your salary,” said Baloun, now chief technology officer at mobile-commerce company Leap Commerce. “I have two kids, and I couldn't do it if I didn't have some savings from this IPO.” Baloun said he has sold about half his Facebook shares and is holding on to the rest until after the IPO. “I will buy a house,” he said. __