The current boom in commercial space flight is being stimulated and fueled by a significant source -- dot.com money. It's ironic that today's challengers to the titans of telecommunications may end up tomorrow toppling the status quo in launch vehicles and manned space flight.

Exhibit one is Elon Musk, the founder and CEO of Space X.   Musk's seed money for SpaceX can be traced to his sale of PayPal to eBay (News - Alert). At the time of sale, Musk owned 11.7 percent of PayPal's stock, a foundation of wealth that enabled him to start up SpaceX, along with side ventures Tesla Motors and Solar City. 

SpaceX just received an additional $50 million boost in private funding, according to a SEC (News - Alert) filing on November 9 which was quickly tweeted to the world.   While the investors were not named in the filing, Musk is the company's largest shareholder and PayPal (News - Alert) co-founder Luke Nosek is also an investor in SpaceX. Founder's Fund, a venture fund managed by Noesk, PayPal co-founder Peter Thiel, and other Silicon Valley luminaries, also has a sizeable stake in SpaceX.

On the other side of the coin, Amazon.com (News - Alert) founder and CEO Jeff Bezos has been quietly -- some would argue secretly -- funding a sub-orbital spacecraft program. Out of site in the wilds of Texas, the Blue Origin aerospace company has built and flown a testbed for its New Shepard vertical launch and landing spacecraft. New Shepard is based upon technology and concepts from the DC-X demonstration built and flown back in the early '90s by the Department of Defense "Star Wars" missile defense program.

A wildcard -- and frankly, a stretch to be called dot.com -- is Armadillo Aerospace. Funded by id Software founder John Carmack, Armadillo has built a number of low-cost vertical launch and landing prototypes over the years to chase Lunar Landing Challenge prize money.   The company has had a mixed record of success, meeting some goals to collect prices while having dramatic hardware failures (i.e. explosions) during other attempts.

Two space X PRIZE challenges have been funded by dot.com style money. The $10 million Ansari X PRIZE for suborbital space flight was funded by Telecom Technologies Inc. (TTI) co-founders Anousheh and Amir Ansari; TTI was bought by Sonus Networks (News - Alert) in 2000 for $550 million in stock. Meanwhile, the $30 million Google Lunar X PRIZE is still up for grabs, with 23 officially registered companies competing to be the first to put a privately funded robot on the moon and transmit back high definition pictures and video.