Once again a relatively easy tool to use to create search facilities on specific topics. The topic search engines provided on the site are American but if you want to use one of these they can be modified by adding sites chosen by you or the entire list of sites can be replaced with sites of your choice.
For a website devoted to a single subject interest or theme, creating a facility to search for a topic on a number of useful sites in one search could be a useful resource for researchers.
When searching you can select the search engine to be searched or just one of the sites searched by the search engine.
Rollyo includes the ability to search the web in the selection of sites in the search engine created which can result in unwanted items in the result list. You therefore need to be specific when undertaking a search.