Polling system Serno?

We've found that we can pull the system serial number using dmidecode for the serial number field...

How can we display those results in the logon screen of our Desktop clients? We already utilize a banner, could we append to the banner somehow?

Trying to devise the simplest means of displaying the unit's serial number at the logon screen. The users won't have access to the BIOS, and we're concerned about the eventuality of the SN label wearing off.