Interesting idea but funds and individual investors alike can only be expected to invest so as to procure financial gain for themselves or their share clients or fund participants.
Socially conscious mutual funds smack of what you propose, and i encourage you to dig into them. There are many and quite a few are doing relatively well, truth be told, in terms of actual returns in addition to achieving their purpose of socially responsible investing. Also, the more people turn to these funds, the more influence they will yield in the market place.
One question: why are the companies undervalued? Maybe they are because they are doing something wrong are in an unprofitable area, or any host of reasons. Should we really prolong the inefficiency or even keep them on life-support to let nature (i.e.: the markets) take their course,.
The tough love approach, you might say.
Here's another idea for you, and i actually believe this a lot:
How about people invest responsibly for the long haul, with an eye on a secure retirement even many years away, and with the hope of self-sufficiency through responsible saving and investing for many happy years of that retirement. Such a citizen will not be a burden on society and will actually contribute to the economy and help support others in need of it.
I am not saying this is in exclusion to your way of investing, I am just saying that is another issue touched upon in this speculative craze under discussion.