Hi Adrian,
You can display ALV cell as push button.
Check this documentation on how to do it.
http://help.sap.com/saphelp_erp2004/helpdata/en/88/387f380c2f2e3ce10000009b38f8cf/content.htm
And in the user command, for the event triggered by the push button, you can give a status message displaying the long text! (The event is BUTTON_CLICK, handle it the way you handle the event hotspot_click)