How to promote research commercialization? What efforts have there been to promote research commercialization (e.g. connecting researchers with investors interested in commercializing the researchers' research) and how are these done?
In the US, at least, there are lots of different mechanisms intended to try to facilitate commercialization.  The major players are:


Universities, who want to make money by licensing patents
Entrepreneurs and venture capital groups, who see new technology as  one of the best sources of profitable market disruption.
Large established companies, who want to acquire new technology in order to prevent their markets from being disrupted and to disrupt their competitors.
Local, state, and national governments, who see tech transfer as a both a major economic benefit and an important justification for investing public money in research.


A few of the many significant mechanisms:


Every research university has some form of Technology Transfer Office, whose job is to get researchers and business people introduced and help them figure out opportunities for commercialization.  Many universities also have "sabbatical for a startup" programs for their faculty, official or otherwise.
Regional associations, like the Massachusetts Association of Technology Transfer Offices or the Northwest Future Energy Conferences do the same thing on a larger scale.
SBIR/STTR programs are a whole family of programs where significant amounts of government grant money is allocated specifically to commercialization of new technology by startups and other small businesses.  Some small businesses effectively set themselves up as independent research institutes with this money.
Within subfields, there are often specific joint industry/academia programs specifically designed to facilitate technology transfer.  For example the Semiconductor Research Corporation is designed to serve as an industry/academia bridge in, well, semiconductor research.  Another example is SynBERC, a long-term NSF project in synthetic biology which includes a highly successful program for industry involvement at all scales.


The interface between academia and industry, in the US at least, is much more intense and complicated than many realize.  You just have to go looking for connections into it.