McDonalds is printing codes on reciepts that give you $10 off any purchase of $29.99 or more.
Go here: http://www.dpgamer.com/
Enter one of the following codes:
413M4D, 4712M9, 4912HA, 48VU64, 4979P3, 497D79, 7DT279, 7K1349, 7L1434, 39458M, 3989XK, 316X7D, 551BM9, 555P6R, 56411M, QD7281, QV3884, R6657X, S737U9, 545Q54, 551BM9, 555P6R, 56411M
This will generate a $10 off promo code to be used on Origin's site. Battlefield 4 is $30 on PC today, so this will drop the price down to $20.