Well my best airdrop of last year brought me $800 worth of optimism coins. If i hadn't dumped them on the market immediately, it would have been $5k lol.

In 2024 I am focusing solely on Prom Testnet Campaign. It really takes a long time and needs to be done daily, but I trust the reward will be worth my time.
It really is not that hard to claim tokens from the faucet, make transactions and mint NFTs - basically your standard testnet activity, and since it is done with test $PROM, it can be done infinitely, for as long, as you got the patience.
And the reward pool is 1 million $PROM upon the launch of mainnet, so I am highly enthusastic about it.
But it would be a little more complex to evaluate the profitability of this airdrop, because the tokens you will receive will not be for external use - meaning you won't be able to sell them or trade them. But you will be able to use them for community governance, partaking a share (30%) of the network profits. So instead of a signle dhunk of money you are actually getting means to making money each month for years.
I hope soon i will be able to report to you with real figures, since the mainnet is expected to launch soon. Until then i still have time to push my rank on the lederboard a bit higher.