Nowadays many ICOs offer free coins, but we have two problems with this free coins, the first one the value of this coins will drop after start trading due to a lot have free coins willing to sell it, and the second they ask for your ID (KYC), and i think it is very risky to send your IDs to any one.Please vote to help others
Before, I can suggest to participate airdrop but now I dont think its the good idea anymore. Due to many reason; not profitable anymore, no guarantee the project will ever survive the competitive market if its not a scam. If they are legit and give reward opr airdrop then its not that big since you must do a referral task to acquire big reward.