Often, I find myself looking for pieces of conversation based on a keyword I remember. Or, I want to quickly see all the lines where <user> has spoken. The best way of implementing a search like this is to highlight all occurances of the words with colors that stand out. It is one of my favorite features showing up in software today, used by Google, Firefox, and EmEditor to name a few. For me, it saves a ton of time.
Preferably, this would be a completely customizable/scriptable/cmdline feature where you could highlight different words with different colors, or have multiple searches running simultaneously.