You can earn free FarmVille goodies such as Fuel refills, Unwithers, and Trubo Chargers when you play Zynga slots.
As you level-up in Zynga Slots, you will unlock free rewards for use in FarmVille.
Zynga Slots Level 2: Unlocks 50 FarmVille Fuel Refills
Zynga Slots Level 5: Unlocks 1 FarmVille Unwithers
Zynga Slots Level 8: Unlocks 3 FarmVille Unwithers
Zynga Slots Level 14: Unlocks 30 FarmVille Turbo Chargers
Here's the announcement from FarmVille:
"Play Zynga Slots to obtain 50 refill fuels (level 2), 1 unwither (level 5), 3 unwither (level 8), and 30 Turbo (level 14)."
The link to get started can be found below. Simply click on it to visit Zynga Slots and start earning your FarmVille freebies.