Realraum tuer instructions:

1. install avr-gcc and tools:
    $ sudo aptitude install gcc-avr avr-libc avrdude

2. download arduino:
    $ wget http://arduino.googlecode.com/files/arduino-0013-linux2.tgz

3. unpack and add link:
    $ tar -xzf arduino-0013-linux2.tgz
    $ ln -s arduino-0013 arduino
    
4. update Makefile variables INSTALL_DIR and PORT to your needs

5. build it
    $ make

6. flash it (press reset)
    $ make upload