I've been working on a USB dongle for Raspberry Pi - a wireless bridge between it and and an Arduino.

All I can say, is that plugging and unplugging hardware can make for some long testing cycles!

Wouldn't it be great ( and easier ) if you could cut out all the extra steps... and work directly on the Raspberry Pi? Getting to the Arduino from there would be one baby step!

The trick then is to get the Arduino IDE running on Raspi. Not as hard as you might think!

From terminal on your Raspi:

wget http://arduino.googlecode.com/files/arduino-1.0.1-linux.tgz
tar zxvf arduino-1.0.1-linux.tgz
sudo apt-get install avr-libc
sudo apt-get install libftdi1
sudo apt-get install avrdude
sudo apt-get install openjdk-6-jre
sudo apt-get install librxtx-java
cd arduino-1.0.1
for i in $(find . -name "librxtxSerial.so") ; do cp /usr/lib/jni/librxtxSerial.so $i ; done
for i in $(find . -name "RXTXcomm.jar") ; do cp /usr/share/java/RXTXcomm.jar $i ; done
cp /usr/bin/avrdude /home/pi/arduino-1.0.1/hardware/tools/avrdude
cp /etc/avrdude.conf /home/pi/arduino-1.0.1/hardware/tools/avrdude.conf

I did run into one hiccup on the Open JDK step... dependency errors - sheesh! So... sudo apt-get update - and repeat the steps that fail. You should be good to go from there.

pi@rasp:~$ cd arduino-1.0.1/
pi@rasp:~/arduino-1.0.1$ ./arduino