When David Letterman switched over to CBS in 1993, the network spent a lotta loot promoting his arrival. One of the less expensive things they did was to lasso Dave into doing a lot of promos for the various local news programs that his new show would be following.
Here's a reel that was sent out so that local stations could build promos that included him. If it gets tedious, zip ahead to about the last five minutes when they have him rattling off copy he clearly doesn't care about…