here you go:
Radio Text
Along with RDS & EON data, some radio stations are also transmitting further information called radio text. This usually gives information on the programme being transmitted and other useful information, phone numbers etc. When selected, this information is scrolled across the radio's display.
from:
http://www.justkenwood.co.uk/editorial/glos_cass.asp
or
http://www.radioandtelly.co.uk/rds.html
something like that
Ps Radio 1 had it.