You can already do parlays..
Event: NFL Week 2 Parlays
Outcome: AFC West Rules (Raiders, Chiefs, Broncos, Changers win) 25-1
Outcome: The Dirty Bird gets the worm (Falcons, Cards, Eagles, Seahawks win) 10 - 1
Outcome: NFC Rules (all NFC teams vs AFC teams win) 50 - 1
Outcome: AFC Rules (all AFC teams vs NFC teams win) 50 - 1
Outcome: Raiders, Lions, Packers, Niners, Bucs, Giants win 20 - 1
Then when the week is over, you payout any of the parlay's that are TRUE.