#StaySAFU is a popular phrase in the crypto world that means 'stay safe'. It originally emerged as a meme after Binance used the term in a security advertisement, and then created the 'SAFU Fund' (Secure Asset Fund for Users) to protect users in case of emergencies. Since then, 'Stay SAFU' has become a fun yet serious way to remind people to take precautions: use 2FA, store your private keys, and be wary of scams. In summary, it is the 'take care' of the crypto ecosystem.