Setting permissions on serial port

[Duane Clark <fpga@xxxxxxxxxxx>]

I have one of those USB serial port adapters, but whenever I reboot, I 
find that I need to, as root, change the permissions on /dev/ttyUSB0 
before I can run minicom. I tried adding a command to do this to 
/etc/rc.d/rc.local, but this sometimes seems to work and sometimes 
(mostly) not.

Is there some standard way to set the permissions on the device file 
when it is dynamically created?