command line program via arduino bootloader

Is there a way to load a program onto the ATmega chip via arduino bootloader from the command line? I don't want to use the IDE. I want to dynamically load different programs via the serial port from another computer. I realize it is possible, however, is it already practical?

If you set your Arduino IDE to verbose mode, you can see the syntax the ide uses to upload to the board. It's actually a commandline tool (AVRDUDE i think) that is beeing called.