Right now they are on sale at Target and Publix for $21.99. There is a Target coupon for $4 off and a manufacture coupon for $3 off. So you can get for as cheap as $14.99at both stores as long as that Publix takes Target coupons (each store varies). There is also a $3 off Publix coupon too so if you don't have a Target near you can get it for $15.99 using both the Publix and manufacture coupon.
I bought one today and will be using in conjunction with a Brita Pitcher because our water is that bad.
I don't know if this is a great price or not but this is the cheapest I have seen them for (with coupons).