Would love to be able to filter either by NULL or NOT NULL. This can filter fields in a table that have a value or don't have any value.
Very useful for example, when working with contacts, and you want to filter only by whether has a phone number, or address, or doesn't. Or in my particular instance, filtering based on whether there's a value in a custom field or not to isolate contacts using a particular product. Tags kinda do this, but this makes sense as a filter option, and would work regardless of whether a tag is or isn't present.
There's a "<>" option, but can't seem to trigger this to display all fields with something, or nothing.