Sometimes the spaces are called labs and contain equipment and tools otherwise unavailable to patrons, but often they are rooms dedicated to hosting a writing group or knitting circle. The important aspects of a makerspace in the library is that it is a place of creativity and collaboration. Check your local library's newsletter or website and see if they are part of the trend toward makerspaces. Also, this post on The Unquiet Librarian blog has links to much more information about makerspaces and their creation and some generally fantastic ideas about how they tie into participatory learning.
Image: danwoog via google