BabyBjorn Potty Chair for $12.99.  Here is a screenshot for your reference.  Shipping is free on orders over $25.  If needed, use this Filler Tool to pad the order to qualify for free shipping.  At the time of this post, 329 out of 378 user reviews have given it 4/5 and 5/5 ratings.  Most places have it for over $20.

This deal has expired as the price has been raised.  Congratulations to those who were able to get in on it.