>>>Here's one: we needed SQRT in Crystal a while back, but they had none.
>>
>>Wait a sec, then (in this Example) Christof's or my awnser would have worked?
>
>No, I'm sure we tried that right after we couldn't find the SQRT() function, and it either didn't work, or else there was no power operator at all :) BTW, was my solution the only one that didn't also rely on a power operator?

You missed mine then.

Mine is the "you know the range the value has to fall in so divide the range in two until you get it" type of solution. Though Newton did it better than me.