I signed up for the Denver Zoo 'Penguin Encounter', part of their new Animal Adventure program.
It cost $95 and consists of a 1.5 hour guided tour, that revolves primarily around the Bird
World exhibit, and ends with a private meeting with a penguin.
They also make creative feeding thingies for some of the birds,
especially the Kea (from New Zealand).
I saw one in the wild a few years back, on my trip to New Zealand.
They do this because the birds are intelligent and it stimulates their minds.