http://ew.com/tv/2018/07/05/david-letterman-sent-michael-ian-black-a-nice-note-after-ed-ended/

Letterman's Worldwide Pants produced the hour-long NBC small-town drama (https://en.wikipedia.org/wiki/Ed_(TV_series)) that ran from 2000 to 2004 and starred Black along with Tom Cavanagh, Julie Bowen and Justin Long.