Chad Beggs' site in which he showcases some playsets he's designed and built for Heroclix figures. Besides the Baxter Building, he's also built the Daily Bugle, the Batcave and a warehouse. What's more, he's got the designs and art available as downloadable PDFs so you can make your own.
Theoretically, these would also work fairly well with Minimates figures if you just wanted a backdrop for them.
Some really nice work, and I doubt the photos do them justice.