I present a little bash script to change the alphabetical order in a specified or working folder of files, simply adding a random prefix and checking that the resulting one differs from a fixed number of previous elements. I wrote it to shuffle a list of songs that I usually listen to my poor car radio, but I think that it could be useful also for presentation of a series of pictures via usb pen and a TV. In addition this script has a clean option that can rename the files to the original version, useful for make another mix.
I happen very often to convert/resize/rename a directory of files, so sometimes I can fix manually file by file or if there are many of the ones, I can modify an existent bash for accelerating the process. However it is a waste of time the changing the whole file to adapt it at the new commands (hazards are always lurking!).