I finally got my hands on a serial spaceball device. Apparently non-USB devices are literally given away on ebay for ridiculously small amounts of money, so I managed to get this wonderful Spaceball 4000 FLX for 12 pounds a couple of days ago!
I wanted a serial spaceball for two reasons: first of all I meant to add support for serial devices to spacenavd for a long time now. In fact John Stone was kind enough to send me his code to interface with serial spaceballs a long time ago, but not having such a device myself, for testing, I wasn’t very keen to hack at it blindly. Also, I wanted to be able to use a 6dof input device with my SGI Octane2, which doesn’t have any USB ports.
So finally, as soon as I got my hands on the serial spaceball, I went on and added serial support to spacenavd. I haven’t released a new version of spacenavd yet, because I want to iron out some details first, but you can always get the new serial-capable spacenavd through subversion if you need it.