Hilary first higlighted this resource as a news item before we had a web resource category. I'd like to bring it back to people's attention as a web resource because of its value.
The CCDC (Cambridge Crystallographic Data Center) has developed a free version of the CSD (Cambridge Structural Database) that can be used for teaching. There are also several tutorials that are relevant for teaching inorganic chemistry including VSPER, stereochemistry, and hapticity. In addition to the teaching subset of the CCDC database that is available online, you can request the cif for any deposited structure.
A paper on the applications of the CSD in chemical education was published in 2010 and is provided as an IUCr Open Access Article (http://dx.doi.org/10.1107/S0021889810024155).