Post office activity, or a hint to this puzzle's theme

Question:

Answer:

LETTERSORTING

Length:

Similar Crossword Questions:

Office building problem that's a hint to this puzzle's theme entries (see their last three letters)
Special CD release ... or a hint to this puzzle's theme
___ to school . . . or a hint to the puzzle theme suggested by the ends of five answers
"Have a nice day" response, and a literal hint to this puzzle's theme
Bridge player's need, and hint to this puzzle's theme
Third baseman's domain, and a hint to this puzzle's theme
Choice for a dog, as well as a hint to this puzzle's theme
Tip, and a hint to this puzzle's theme found in five answers
Party with too many dudes... or a hint to this puzzle's theme
Small taste or, pronounced aloud, a hint to this puzzle's theme
Middleman (and a hint to this puzzle's theme)
Common refrain that's a hint to this puzzle's theme
Antelope with spiraled horns (and a hint to this puzzle's theme)
Angle (and a three-word hint to this puzzle's theme)
It starts at a plate (and a hint to this puzzle's theme)
Handle user, and a hint to this puzzle's theme
Uncredited actors, and a hint to this puzzle's theme
How long it takes to get something back (and a hint to this puzzle's theme)
Valedictorian's pride, and a hint to this puzzle's theme
Fill in the ___ (a hint to this puzzle's theme)
Delightful, and a hint to this puzzle's theme
First name of a civil rights activist who would turn 85 today, and whose adopted last name is a hint to this puzzle's theme
1997 Kevin Spacey film, and a hint to this puzzle's theme
"That's final!" (and a hint to this puzzle's theme)
Grammy-winning Nelly Furtado song . . . or a hint to the puzzle theme