NFL.com is running a playoff fantasy football game that I entered (it's free) and thought some people on here might be interested in as well, so thought I'd share.
Short description: Each week you pick 8 players (QB, RBx2, WRx2, TE, K, Defense) and get points for them based on their performance that week. But if you use the same player for multiple weeks in a row, you get more points for them (the second time you get a 2x multiplier, then a 3x, then 4x). You actually can start a player who's on a bye in week 1 to get more points later, if you think they'll go far.
The website with full information and where you can register/participate is:
https://playoffchallenge.fantasy.nfl.com/
I created a group called 'Heroscapers', so if you are interested you can join that group (similar to what others have run for ESPN's March Madness brackets in the past).
You would need to get picks in before the first game starts tomorrow (~ 4:30 EST).