Amiga File Transfer
I am new to this forum, just signed up to add my own bit of wisdom to this particular thread...
Personally, I love AmiTCP. It lets you set up the Amiga much like a unix box. It comes with it's own ftp daemon, though you do have to set up the home/user file structure yourself. You can also have it force a login requester before you get to Workbench which gives it the SunOS / Solaris style security and front end. I like it a lot. The ftp server is a bit basic, but once it is up and running you can get to it from any other box, Amiga or Otherwise. I use FlashFXP to get to it from the PCs and have 0 problems. Also, if you have access to AmiForever and AmiExplorer, mentioned in a previous post, it works great across the network. Much faster than a null modem or parnet cable, and you have the added benefit of a decent pc side interface for it.
I put AmiTCP 4.2 on all my Amigas, and would highly recomend it to everyone. People say it is hard to set up, but I had it running in under 10 mins. I am a unix admin by trade though, but would be happy to provide any guidance you may require.