We should at least mention the MKII, a programmer that offers ISP in the same way that the USBtinyISP does, but also provides JTAG, debug wire, and few others. We have no experience with this unit so ...

This low-cost project aims to develop an open-source AVR USBtinyISP programmer with SPI interface that is built around the ATtiny2313 AVR microcontroller. The project has been tested with the ...