Uno and Leonardo can be used as true ISP programmers/basic debuggers for most target AVRs. You do not have to remove any chip and you do not need to burn any bootloader.
The main idea is to use avrdude:
see: http://arduino.cc/forum/index.php/topic,125248.0.html
(Have enough patience and read the topic to the end.)
When I have time I will make a step by step tutorial.