A cool way to comment on some guitar player's tasy licks. Like in Euphoria by The Youngbloods:

Awww, pick it, Wilson.

Note that the guitar player's name doesn't actually have to be Wilson; it is of course a pun on the name of Wilson Pickett, the great R&B singer of Mustang Sally and In the Midnight Hour fame.

Analogous to: "Look out!"
"Guitar!"
"Blow your horn!"
"Sing it!"
"Hit me!"
etc.