MIT GIS Services maintains an international collection of GIS datasets covering a variety of information types, including:
US and foreign census data
Parcel/tax lot boundaries with detailed assessor property data
Land use/ land cover
"The Big Ten Academic Alliance Geoportal provides discoverability and facilitates access to geospatial resources. The resources in the portal are selected and curated by librarians and geospatial specialists at twelve research institutions in the Big Ten Academic Alliance.
The resources include GIS datasets, web services, and digitized historical maps."
"GeoData@Tufts is developed and maintained by Tufts University Information Technology. Tufts is leading the development in collaboration with Harvard of this open source, federated web application to rapidly discover, preview, and retrieve geospatial data from multiple repositories...GeoData@Tufts is part of The Open Geoportal. The Open Geoportal is a consortium comprised of contributions of several universities and organizations to help facilitate the discovery and acquisition of geospatial data across many organizations and platforms."