Send information (such as a string) over digital pins I wan't to send information from my arduino digital pins to another arduino's digital pins like a string, or a char. Can I do this without something like Software Serial?

The reason I am asking is because I am wanting to send information from several serial devices to my raspberry pi from an arduino. Thing is, that Raspberry pi only has one set of UART pins, so I was thinking because I have extra arduino uno's, why not send then information to the arduino and have it write the received information to the raspberry pi's digital pins..

Now that I am writing this, I think I will connect the 2 arduinos via a serial connection, and use software serial to write out to the raspberry pi, in three different stages, to get the information to the pi.

The reason I am using the PI is I want to display this information on a large screen with many different options, in short the GPU capabilities are what I am using the PI for, that and Processing.

Question still stands though, can you send information over digital pins?
The RaspberryPi is a fairly complete linux computer.  As such it can be a USB Host to many USB Devices.  If you need more serial ports simply buy FTDI equipped USB to serial cables, plug them into a USB hub and plug that into the RaspberryPi.