When you send in one Activia UPC to Yoplait- you'll get a coupon for free Yo-Plus. Download the rebate form found here. Get an additional coupon for $1/1 HERE. Yo-Plus is just over $2.00 at Walmart which makes it $.26 a yogurt.
Money Saving Madness is reporting that there will be a coupon for Activia this Sunday.

Thanks, Money Saving Madness.