The always groundbreaking Brooklyn Museum has now released an API to allow the public to interact with their collections data. I can't even tell you how happy I am about this in terms of an open data perspective. Also, this is the direction that makes the whole "detailed curation by passionate amateurs" thing possible.
There are only three simple methods for accessing the data. Ideally, it would be nice to see them put their collections metadata up as linked data, but now I'm daring to dream a little. Hey, wait a minute! I think that's the perfect way to start playing around with the API. Doing some digging through the documentation, I'm seeing that all the objects and creators seem to have URIs. Take a crack at it - the registration form is ready for you.