Automatic Filters

Is there a way to have a filter automatically applied as soon as a filter option has been checked so that, as you check more options, the filtered list gradually narrows down. The final result would be the same as if you select all the options and then clicked the apply filters button, i.e the way the filters work now.

My client is insisting that this is the way he wants the filters to work!

http://wordpress.org/plugins/db-toolkit/