There are many attempts afoot to establish a system of reputation to help strangers trust each other on the web, and of course which can't be gamed! Problems with conventional approaches
It is a very tricky question though because reputation is often specific to different aspects of a person's life, and specific to the context in which it arose. So the approach that tries to aggregate existing metrics gives us a lot of information but we might not know what it means. E.g.
Just heard Matthew McStravick today talking about Economy of Hours, his widening of timebanking to include local businesses.
Running the Timber Wharf Timebank in Hackney, London, he was frustrated by the limited scope of the project which, following donor priorities, had to focus a single social problem.
It is a story that I have told in my own writings and presentations, particularly in my book, The End of Money and the Future of Civilization, but the video below is well worth viewing. I’ve not been a big fan of Glen Beck, and I abhor the Fox network, which I consider to be a propaganda instrument of the global elite, but this particular program is ironically quite good at telling the story of the creation of the Federal Reserve, the banking cartel, and the collusive arrangement between the bankers and the politicians (that pattern was actually established with the founding of the Bank of England in 1694). Beck’s featured guest, G. Edward Griffin, the author of The Creature From Jekyll Island, is particularly astute in his observations. The conversation only goes astray toward the end when it turns to gold backing, a proposal that is based on a still naive conceptualization of what money is and how it works.
Interestingly, Beck was fired by the Fox network shortly after this program aired, presumably for exposing the scam of the elite cabal that Fox is there to serve.