Best way to abandon usable code?

[Joshua Isom]

I've recently wrote some code and programs that graph a function(not a 
bunch of points), but it's reached the level that I'll probably ever 
need since I know how to debug any issues and how to make it work for 
me.  There're perl modules for interfacing with something that plots 
points but this actually does a graph of a function.  For anyone 
reading this who's done stuff with electronics, it started out as 
modeling the duty cycle of a 555 timer chip in monostable mode with a 
set control voltage instead of the standard.  It can also handle 
summations(a sine wave merging into a square wave for instance), and 
other things not even possible with most graphing software since it 
works with subroutines and not equations.  I wrote it because nothing 
existed on CPAN but I think the code is something a lot of people would 
use.  I have no tests, but not sure how to easily test a png output, 
since I wrote it all before I saw the Imager module.  Is there some 
best place for abandoning useful code without having to bother 
maintaining it?