BASELINE CALENDAR
I have contributed to baseline calendar,
https://github.com/eea-oasis/baseline/tree/main/examples/calendar previously. 

ZKCASH
Receive payments anonymously via a link [ Created a circom circuit for creating link ]
Send payments anonymously to another account [ Created a merkle tree circuit for sending payments ]

VITEPAY.JS 
Create a react SDK to integrate to vitepay payments with any react based Dapp. Total 600+ downloads till date.
https://www.npmjs.com/package/vitepay.js