Dynamic classes for query loop items

It would be very useful if it could be optionally configured in the query builder to dynamically add classes to each list item based on different taxonomies (or other conditions, e.g. custom fields). This would be cool for several reasons in my opinion:
1, the Filterable container block would be much more dynamic (preset categories or other taxonomies – i.e. preset specific classes – could be dynamically filtered even for expanding content)
2, with a bit of CSS, certain elements could be highlighted, for example a different background for elements in category \’XY\’