The value of viewing the cache at Google for a view of the indexed page really registered with me on this search. I was looking for biographical information about a Canadian author – and finding very little. This query got a good hit from the Archives of Ontario as we can see in screenshot of the snippet below, but the actual page blocked my access. This is, by the way, an example of “invisible web”, where the information is buried in a database – you need to know the database. But Google had indexed it and a click on cache revealed it.
Remember to mouseover the chevrons on the right of a search result to see the preview and find the link to cache.