Amazing engine - It produced results for almost anything I typed in. Elliptic integral, derivatives and what not! Beautiful! I am really humbled by the creators of this Engine!
Google search as well as live search has a nice feature where you can enter equations like 72*34 or e ^ -2 which will return the answer.
In fact Google goes one step further. It even handles queries like "seconds in decade", 70 farenheit" [which I need all the time, because I don't have any feeling for farenheit!]. Seconds in decade didn't work in live search.