Hyla (in ‘overuse of acronym’ thread) made the interesting comment:

Perhaps this stems from the fact the English has so many different pronunciations of letters, based on what they're next to, combined with, etc

So here’s your first challenge of the millynumb, peeps!

Your mission, should you choose to accept it, is to determine: how many combinations of letters are there in (more-or-less) standard English that can make the “sh” sound?

You have 7 days from now, with suitable prizes awarded according to complete whim…