Using isv.config customizations you can add buttons to the menybar above a grid (next to “More Actions”). A special technique has to be used to fetch the selected records and Ronald Lemmen wrote some about it this summer, here: http://ronaldlemmen.blogspot.com/2007/06/fetching-selected-records-in-grid.html . I had reason to try it and ran into problems when the url of the file containing the javascript was on a different server (different tcp-port has the same characteristics as a different server from an IE viewpoint). The window.dialogArguments was null. I tried to modify the settings in IE but found no way of getting around the problem except for setting up a virtual directory bellow the CRM-site containing the html-file.

So, if you run into similar problems, try moving the html-file to a directory on the same server (from an IE standpoint).

Gustaf