A part of my academic research involves the searching of large collections of texts for key words. Following a presentation I saw earlier this year in which the textual pattern matching was being applied to the textual analysis of Chinese classical texts, I was inspired to cook something up myself using my own pet Gtk+ project, Gnocl. Here's a screenshot:
This project particularly shows how relatively nasty jobs such as over-riding the basic style settings for the treeview widget can be done in Gnocl. Both Gnocl and Gnocl GrepGui are avialble for download from Sourceforge.