Mysterious Google barges continue to pop up

LOS ANGELES -- Not one but two secret floating barges have now been tied to Google, but what could they be?

In the past week, the Mountain View, Calif., tech giant was linked to a company that has leased out a hangar in the middle of San Francisco Bay where it is building a mysterious structure behind tight security.

That same company is building a similar floating structure in Portland, Maine, that is also "shrouded by the same high security and mystery" as the barge in San Francisco, according to a Monday report by the Christian Science Monitor.

Google has yet to comment on the matter, which adds to the belief that the Silicon Valley company is involved with mysterious structures.

It isn't obvious what the structure may be, but there are a few theories out there for what Google could be building. Here's a list of what has been reported as well as our own far-out predictions for what Google could have in store.

A floating data center

CNET was first to uncover Google's connection to the floating barge, so it was also the first to throw out a theory. The tech news website believes Google could be building a floating data center. The reasoning for that is because in 2009 Google was granted a patent for exactly that kind of project.

Google is known for thinking outside the box -- it's working on self-driving cars and Wi-Fi balloons -- so this wouldn't be the craziest idea ever.

For more on this CNN story, click here.