Password protection isn't particularly easy on the Amiga. You'd basically have
to put it into the program code itself. Or you can encrypt the program and
then decrypt it before you ran it, but that would be awfully complex.
If you don't have a hard disk, the easiest form of protection is to put the
floppies where people can't get them. (The same applies for a hard disk…
Just keep the protected programs on the floppy instead…)
Before you get disillusioned, Password protection is just as difficult on any
other computer, so it's not an Amiga specific problem. I'm glad you love your
500…. I wouldn't be parted with my Amiga for any reason whatsoever…
–>Steve Bennett
P.S. If you do want to go the encryption route, I seem to recall that the Amiga
version of ARC (ARC023.EXE over on AmigaTech, DL4, I believe…) has optional
encryption capabilities…