File sync software


 * https://www.bogleheads.org/forum/viewtopic.php?p=3734411#p3734411


 * Goodsync * https://www.goodsync.com/how-it-works
 * Backblaze
 * FreeFileSync * https://www.freefilesync.org/
 * Arq * https://www.arqbackup.com/
 * synctoy
 * Windows 10 has a good built in file backup software suite
 * rsync * rclone https://rclone.org/