This is actually you receiving 0.001 and attached is a memo.
Basically bots use it as a way to advertise, you get 0.001 and they get you to read some spam message. Be careful though these "gifts" can often contain scam attempts.
You can also send private messages in the same way, if you start the message with a #.
Good to know -- thank you for your insights. It feels scammy, so I will steer clear.
i didn't understand how to send private mess. thx
It's pretty easy. You need at least 0.001 SBD to send a message. I just tested two private messages to @kirkins: one with 0.001 SBD. That went through. There was a transaction error, however, when I tried to send a message with 0.000 SBD.
i undestand