I saw this adorable Recycled container piggy bank on Babble.  I think I'll use a Downy container since it already has a pink cap.  It should be easy to paint or spray paint the blue part.  And I'll add some googly eyes and use some small cardboard circles for the legs.

Teach your kids how to save money and the earth by transforming an old softener bottle into this adorable piggy bank! Just add embellishments for the ears and eyes, cut a slit in the back, and your kids will be saving in no time! Plus, the built-in handle makes it easy to tote your riches around.

There are some other cute piggy bank ideas on Babble: http://www.babble.com/crafts-activities/8-fun-diy-piggy-banks-get-saving/