Investing in space-related projects can lead to patentable breakthrough$ in energy production, the biotech sector, robotics, mining, metallurgy, chemistry, and telemedicine (to name a few).   There´s also the goodwill associated with inspiring students to eagerly embrace math & science again.  
    Here are the websites of known companies with substantial activity in the space investment realm:
   

Exoventure

FirstBankOfSpace.com

Florida Aerospace Finance

Futuredex

Global Science & Technology, Inc.

Jeffries Quarterdeck Investment Partners

Lunar Stock Exchange, the first ever extraterrestrial securities market
and the leader of a Moon colonization and space tourism campaign,
offers an opportunity to invest in the future.”

Omicron Aerospace Investment & Development Corporation

SpaceVest

Wilshire Associates
(founded by the world's first space tourist, Dennis Tito)

Any others?

Relevant publications:

HobbySpace.com
(with an impressive space investments section)

Space News: Business

SpaceEquity.com

SpaceInvestor.com

Space-related legal reforms

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