There are currently two codes worth 125 free Kellogg's points – JOYFULPOINTS4YOU (exp 12/17) and HOHOHOLIDAYBONUS (exp 12/14).
Kellogg's is also running a holiday raffle through 12/21. Simply head over and spin the wheel to see if you win 50, 100, 500, 7500, 10000, or 100000 points! You can spin daily for more chances to win free points.
After logging into the site, head to the homepage and look for the massive banner above.