design ideas - Coffee plunger

I have friends who can't seem to plunge coffee without jetting it all over the table.  They get too impatient and push down too hard - ahem.  Whilst this may be a comment on a society that is in too much of a rush to even wait for good home made coffee. It got me thinking about improvements (probably gimmicks) that manufacturers could make to their designs, to offer a USP.  There are many ways to slowly depress the plunger, including motors and wind up mechanisms, but in the end I settled for a weight that could be placed on top of the plunger once the coffee had brewed for the required amount of time, so that our friend gravity could be left to do the job.  The coffee will no longer jet, but in regards to the manufacturers, it probably won't fly either.