Popular playback footage includes sports, news and weather, exercise instruction, old black and white movies, cooking shows or nature footage.  Some examples: At a TGF crowded bar scene, a monitor shows a soccer match, on the set next door a dialogue between the two stars of a new romantic comedy shows an old movie playing in the background. Or a family living room scene where a nine year old flips through channels from chefs sauteing fish to a western shootout then the local weather to finally her favorite cartoon show.  Other background usage includes greenscreen footage to place a character standing on a Hollywood set into an exotic location across the globe or even chased by an angry rhinocerus   The period and locale choices are endless.  

The selections below are merely a starting point, you'll find more related footage by doing your own original searches, tailored to your needs!