Add the below to your /etc/apt/sources.list
Update and a new version of onBoard will install. It includes a few fixes and the ability to specify where onBoard will appear on the screen.
deb http://ppa.launchpad.net/onboard/ubuntu feisty main restricted universe multiverse
deb-src http://ppa.launchpad.net/onboard/ubuntu feisty main restricted universe multiverse
To start onBoard in GDM (Ubuntu) insert the below in /etc/gdm/Init/Default just before exit 0, for KDM (Kubuntu) add to the end of /etc/kde3/kdm/Xsetup
Note the numbers will depend on your size of screen so play with them until you are happy.
exec onboard -x 0 -y 470 --size=800x300
GDM has to run either as "plain" or "plain with face browser". Configurable in gdmsetup.
For Gutsy users replace all instances of feisty with gutsy