The Rainbow Barrel is a small wine barrel filled with rainbow colored apples. Don't be deceived by the game's free gifts page, farmers. Even though this item doesn't have "Limited Time" written underneath it (as of this writing), some in-game text confirms that it won't be around forever, so you'll want to send and ask for as many as you can, while you still can!
With the past few weeks seeing a resurgence in these formerly exclusive items, as they're being made available in other ways (the Silver Pony can be purchased from the store, for instance), it leaves us to wonder if the Rainbow Cart filled with apples will be next. I certainly hope so, and we'll make sure to let you know if that does end up being the case.
Do you already have Rainbow Barrels on your farm(s)? Will you ask for any of these items from your friends before they expire, or do you not care about small decorative items such as this? Sound off in the comments.