Mozilla Firefox-world's 2nd installed browser(No 1 by non-default installations)
Seeking Alpha- world's major free source of investor transcripts
Google- Need I say more?
SSRN -World's No 1 source of academic research-downloadable free(mostly)
Project Gutenburg-World's most used ebook source
Wikipedia- most referred to online encyclopedia
The common thread among these is that the end user does not pay for them. Either the advertisers pay(as in Google/Seeking alpha) or it is run by donations(in Mozilla, SSRN and Gutenburg). We humans suckers for "Free" as any retailer would attest. But "Free" is merely an entry point. Unless there is quality and value addition, even the free websites will not prosper.
When people give their time/individual contribution to create something non-commercially, it becomes a labour of love filled by passion(sadly lacking in many jobs). The Wisdom of Crowds ensures that the overall output quality does not suffer. The above services have not stagnated because of renewal and people giving their time. It shows that non commercial ventures(not including Google/Seeking alpha) still have a chance in today's world