Answering your question about the usage of accelerators, this feature allows you to expose different web services taking the information that you selected in the actual page as a query avoiding the need to copy the information and then open the webpage of the
implemented site to paste it to obtain the result. For example a bank web page could implement an accelerator for currency exchange of diferent countries, in this case you only need to select the number to change and use the accelerator to get the result back
according with the information specified and the currency selected. I recommend to you take a look of accelerators avalaible en the url
http://www.ieaddons.com/en/accelerators and try to see how it works.