This idea is definitely not as elegant as Thor's but if you are looking for a quick way to do it then why not let the OS take care of the multiple instances? It will be easy to write a shell script (couple of lines) that calls your Perl script with the required file arguments many times. If you wanted to process two different routines in the same script this idea will not work but if you just want multiple file handling then the shell might give you a quick solution albeit not so elegant!

 
script file1 file2 file3 &
script file4 file5 file6 &
.....
....
[download]

This also assumes that you are not creating any *static* temp file names (i.e. hard coded) within your script!

cheers

SK