Here is an AppleScript designed to display your current iTunes song on an LCDproc server. It uses expect to control a telnet session to the LCDproc server. You do not need Growl.
You must open it in Script Editor, save it as an application and select "Stay Open" in the save dialog. Then you can put it in your iTunes Scripts folder so it is accessible in iTunes.
Download the iTunes LCDproc AppleScript.
Update!I updated the script so it uses very few processes now.
I have created an LCDproc installer for Mac OS X. It is built for G3, G4 or G5 PowerPC Macs, but I should have an Intel build available soon. Intel Macs will not be able to use it. LCDproc gets installed into /usr/local/. A start-up script is included in /Library/StartUpItems/LCDproc. It is pre-configured for the Mac OS X USB LCD Kit. Once you install, just restart as instructed and LCDproc should be running on your Mac OS X USB LCD Kit. If you don't have the Mac OS X USB LCD Kit, you can edit the configuration file in /usr/local/etc/LCDd.conf
GrowLCDproc 1.3.8 is now available for download.
GrowLCDproc 1.3.8 adds true coalescing support, iTunes ratings support and improved display format. This means you will no longer get multiple screens for different songs if you skipped a song once it started. Also, the number of stars you have given a song will be translated by GrowLCDproc into asterisks. A marquee scroll is now used to improve readability for longer single-line messages. Finally, vertical scrolls have had the speed reduced and horizontal scrolls have been sped up slightly.
The source will hopefully be incorporated into LCDproc and I should have a compiled download available shortly.
THe default set up is for winamp wiring, but the MAC OS X USB LCD Kit is wired a bit differently. Make sure to uncomment://#define USS720_MAC_USB_LCD_KIT_WIRING 1
to enable the proper wiring for the kit.
Update: 8/10/2008
The hd44780-USS720 driver code has been incorporated into LCDproc. I hope to have a compiled version available for download as soon as possible.
I have just finished an LCDproc driver for the Mac OS X USB LCD Kit. Sorry for the long delay on this, it had always been something I wanted to do. It should be incorporated into an LCDproc release soon.
The driver uses libusb, so it can be used on any OS supported by LCDproc. If anybody who purchased a kit is interested in testing it out, please email me.
GrowLCDproc now works with Growl 1.1.x!
Take a look at the documentation.
Download the latest version now.
Look at some previous posts for more details.
After some final feature improvements and bug fixes, GrowLCDproc is now available for public use!
Forward Growl notifications from your favorite Mac OS X applications to any number of LCDproc servers running locally or on remote networks. Then see your Growl notifications appear on any of the displays supported by LCDproc on a Mac OS X, Linux or BSD server.
Take a look at the documentation.
Download the latest version now.
Update!
GrowLCDproc 1.3.1 is now a Universal Binary.
New GrowLCDproc available with improved sleep behavior. Fixes a bug where sleep would cause a bad stream to remain open and prevent screens from being sent to LCDproc until a "reconnect".
I just submitted some code to get a serial Point of Sale display working with LCDproc. My display uses the AEDEX protocol and seems to work great. I will post the code here shortly.
When used in conjunction with GrowLCDproc, you can show your current iTunes songs or any Growl notifications on the display.
Update!
The LCDproc distribution now contains this driver with the name serialPOS. I have also added a feature to allow input from an RS232 keyboard or terminal through a serial pass-through port.
I am easily amused I suppose. Trying to find a use for the old compact Macs I have around (Macintosh 128K, 512k, SE, SE/30), I set up a connection (see below) to my G3 and ran the LCDproc daemon from the old Mac using curses as a display. Using my GrowLCDprocDisplay program, you can even display your currently playing iTunes songs!
Basic steps for a serial connection:
tty.usbserial "/usr/libexec/getty local.9600" vt100 on