It's sending Bitcoin on the Lightning Network. Depending on what Client app you're using, they show up a little differently.

Duri6 Thur and Fri at 5pm-530pm EST we have a #zapathon where people post things with that hashtag and get zapped. Sometimes a few satoshois, sometimes 1000s

Get yourself a Lightning Wallet and add the Lightning Address to your profile, and people can zap you too! 🤝