A few projects have done this (although more recently with EOS and Ethereum). The only notable one I can remember off the top of my head is Clamcoin:
Every person who had Bitcoin at block 300,377, Litecoin at block 565,693, or Dogecoin at block 218,556 was given ~4.6 CLAM.
This has spawned a few digging services over the years, where you can upload old LTC, BTC, or Doge wallets (after removing those coins, of course) and get Clamcoin out.
0.000000007777777777 ETH to some
174,655 addresses as a marketing gimmick for an ICO called Safe. Many other Ethereum ICOs conduct air drops, usually with some rules like "Any address that sent or received ETH between X and Y blocks".
More recently, some EOS projects have been "spamming" free
0.0001 EOS to various accounts
I do believe that Clamcoin is the only major example of distribution based on community participation at that scale, though.