I can't seem to find any resources relating to the implementation of SO's interesting tags javascript implementation, where adding tags happens on the client-side, and you can delete tags on the client-side also. It's just I'm looking for a way to select multiple entities for use in a query, without using a multi-select list (combo box?). The tag-style format is very useful. This is also similar to Facebook's messaging where you can specify multiple recipients.
Any pointers?