Pony Prog still works on Win7 (so I've read). See:
http://ponyprog.sourceforge.net/phorum/read.php?2,2249You might be surprised to see that your modern computer actually has a real hardware serial port. It is unlikely that there is a DE-9 connector on the back panel, but there might be a header on the motherboard to which you attach
one of these. Check the documentation or look for the port options in the BIOS (you may need to enable it in the BIOS before it will work). I don't know how well a USB-serial adapter will work since ponyprog probably toggles the handshaking lines at a high rate. It may or may not (probably slow if it works at all).
Bus Pirate will work to read and write the EEPROM, but you won't be able to just load and burn a .hex file. Bus Pirate is intended as a console device, giving you command-based access to the I
2C bus. So you can issue the appropriate commands to write data to the EEPROM or read from it, but it doesn't do this automagically. A person could certainly write a script to parse a .hex file and create a listing of commands to dump into the Bus Pirate terminal window...