A handy module, and pretty unique on CPAN for better or worse. Uses basic GD functionality which is generally widely available on most platforms. There's no real test suite, and the documentation is simplistic -- but to be fair, there isn't much documentation required. Just be sure to set GD::Image->trueColor to false if you've previously set it to true, or you're going to be fighting with black images until you get that light bulb.
Excellent, yet elegantly simple module. Takes a bit of a speed hit over Thread::Queue due to the serialization of data structures, but gets the job done with ease, and is almost a direct drop in replacement for Thread::Queue. Two thumbs up.