Crosswordiee.com

% replaces any number of letters (la% - lake, lamp)_ replaces one letter (ca_ - car, cat)

Crossword clues for 36-Down offering 4 letters:

WIFI: 36-Down offering
LETMETAKEYOU: Corny offer, with 36 Across
NOFEE: With 36-Across, Craigslist offering, for short