The number of times on uncontrolled frequencies I hear "ABC, abeam Smithville, 3,000ft". Useful position information right there.
Not a radio call as such but an exchange I was involved in with a student not particularly long ago:
Tower: "ABC, continue downwind number three behind a 172 and a Tomahawk"
Student Bloggs: "continue downwind, two aircraft ahead in sight, looking for number three"
Me doing my best to stay deadpan: "That's us, Bloggs"