ObjectSpot gadget (OpenLearn version)
ObjectSpot  is a customizable federated search engine querying multiple digital libraries.
ObjectSpot Gadget User Guide
The ObjectSpot Google Gadget for the OpenLearn test-bed is available here: 
You can add the gadget in your iGoogle page from this URL. Once you add it, you can use it as a standard search engine. You can search for keywords and the results come from the following sources:
You can choose to exclude one or more of these sources by clicking on ‘Options’ (Figure 1). From there, you can also change the way the search results are sorted.
Figure 1. The options of the gadget
Figure 2 shows the search results for ‘sustainable energy’. You can check how many results you got from each source by hovering the mouse over the status indicators on the top right corner of the gadget.
Figure 2. Sample search results