UDPcast is a file transfer tool that can send data simultaneously to many destinations on a LAN.
This is https://www.udpcast.linux.lu/index.html, every version from https://www.udpcast.linux.lu/download/ imported as a commit plus some fixes that I needed (ex: speeds above 2GiB).
TODO: Check and improve other options' parsing (many hapily accept negative values and hang forever).