not much hope of applying it by law on all, simply because to make it work it would ned to be done multilaterally on all companies.

Not sure how you will persuade or compell some chines or indian company to do this.

whose idea is this 'robin hood tax'? where can i find out more info as to whether it is pie in the sky or do they actually have a method whereby our national gov can press for multilateral/multinational imposition of this tax?