This is a follow up to this closed question.

I open a random page, such as something on arXiv at 8:05 p.m. EST, and I see all these dollar signs, and I sigh and I wish that I could see nicely formatted math formulas instead, just like on MO. Is it possible? Can one write a Greasemonkey script to apply jsMath after the fact even if the page authors did not think of it? A Mozilla Firefox addon?

Now I am not smart enough to figure this out, but if you can then all the karma and points to you. Please share. Seeing like this is an active community of people with similar interests, I am sure that hundreds or thousands of mathematicians would benefit from a solution.

Editor's note. I tamed the first paragraph while trying to preserve the core meaning. Note that this follow up question was suggested by myself and others when closing the original question. (François G. Dorais)