It would be nice to have a search & replace within math mode.
It could work document wide or only in currently focused math-box.
It would allow you to search and replace via latex commands,
for instance, search ^{2} and replace with _{2}.
Maybe the search box itself could have a math-editor so that you don't
have to enter latex.
Can be nice if suddenly in the middle of a calculation you decide you want
to go with another convention for notation.
So far the way I do this is by editing the lyx source file with vim,
so it cannot be _too_ hard..
I guess the main hurdle would be the extra GUI box.
