I would like to progam an ATMega8 to run without a crystal. I am reasonably confident that I can set up my current UNO to act as an ISP with optiLoader, which conveniently has an image for an ATMega8 boot loader built in.
I think you need a bootloader suitable for use at 8mHz (or whatever internal clock speed you decide on). I burned a couple of ATmega8 chips using ArduinoISP on my UNO v2 board and they work well. Only small gripe is the bootloader is old and waits about 8 seconds from reset to starting the main program but it does not matter enough to de-solder the chips and put a better bootloader on as they only get re-booted once per day at most.
Did you ever try the Optiboot bootloader that I posted?http://arduino.cc/forum/index.php/topic,116404.0.html