The latest MiniPOV kit is for serial ports so more people can use it! If you have a parallel port, you probably want a MiniPOV2 which is identical except for the port used.

A simple POV toy for beginners who are looking to learn how to solder, how to program microcontrollers, or make LED blinky toys. Because the programmer is built into the kit, one does not need a special "microcontroller programmer". This version can be used with PCs (Linux/Unix or Windows) and Macs (running MacOS X and with a USB/serial converter).

This kit can definitely be used with a USB serial port converter on MacOSX/Win/Linux but I can't guarantee it will work with just any converter you use. It has been tested to work with the USB/Serial adapter in the shop and other PL2303 and FTDI-based adapters. 
If you're using a MacOS X and a "Prolific PL2303" chipset USB converter you should download and install the PL2303 OSX driver available here instead of the one on the CD.

Don't forget to read the instructions over at ladyada.net!