NearDrop - An unofficial Google Nearby Share app for macOS
PairDrop - Local file sharing in your browser. Inspired by Apple's AirDrop. Fork of Snapdrop.
Snapdrop - An open source alternative to Alternative to AirDrop.
Sharik - Sharik is an open-source, cross-platform solution for sharing files via Wi-Fi or Mobile Hotspot
Send Anywhere - Send whatever you want, wherever you want
LocalSend - An open source cross-platform alternative to AirDrop