Depends on what I'm transferring and to/from where:
scp
is my go-to since I'm a Linux household and have SSH keys setup and LDAP SSO as a fallbacksshfs
if I'm too lazy to connect via SMB/NFS (or I don't feel like installing the tools for them) or I'm traversing a WANrsync
for bulk transfer and backups- Snapdrop/Pairdrop for one-off file/text shares between devices with GUIs (mostly phone <--> PC)
- SMB if I'm on a client PC and need to work with the files directly from the fileserver
- NFS between servers
- To get bulk data to my phone (e.g. updating my music library), I connect via USB in MTP mode and copy from the server via SMB or sshfs.