How about like… a sorta Cow themed piñata as the chest? Maybe even give reference to HCG staff?
Arioche’s Cloche, Stash of Hoof’s Hooves, Grim’s Grimmer Glimmers? Maybe even run a player contest to have them design and come up with good chest ideas/contents? The Titan Design was a fairly solid hit, so why not?
Could be fun. We'll see. 
~ Grim