[Minifloat] is using his TI Launchpad development board as an In-System Programmer for AVR chips (translated). There are a ton of homebrew AVR programmers out there, and using an Arduino for ISP ...

[Texane] wrote in to let us know he has implemented AVR ISP programming using a PIC microcontroller. He wrote some code for an 18F4550 that uses the STK500 standard for In System Programming.

"While no programming is required— the microcontroller ... microcontroller can be reprogrammed in circuit with an AVR ISP programmer, such as the USBtinyISP, to make either minor or radical ...