If having problems reading:

• Read chips 2 or 3 times to make sure its reliable. Re-seat between reads
• Polish pins to remove oxide layer. One easy trick is to slide back and forth in the ZIF socket (at the cost of wearing out the socket a little)
• Heating chips may improve reads (“heat the chip up till you can't touch it its so hot, then with tongs put it in the dumper (er, maybe not quite hot enough to melt the textool socket), that will raise the ambient energy of the floating gates on the chip (temporarily, until it cools down) which may make it read better”)
• Undervolting may improve reads (“also i don't know if the bp software lets you do this but if you adjust the vcc level downward of the chip while dumping you can often see more data than you would”)

From anonymous source.

USB, think they cost something like $100.

A programmer JM use to have. Programmed via serial port. It seemed quirky and my particular unit seemed defective/unreliable. Doesn't look like I have a picture of it handy. Scrapped.

Very common low cost adapter. Driven through parallel port