On a Mac:
- Navigate in the usual way to ~/Library/Application Support/Second Life/<your name> or wherever you keep your chat/IM logs.
- In the usual search box at top right type ".txt" (without the quotes), and select File Name search, to display your chat log files. OK this will also display typed_locations.txt and search_history.txt, but you can deal with that, right?
- Click on the search bar Save button to save your selection as a Smart Folder under a useful name. It will now appear in your Finder sidebar.
- Click on the Smart Folder icon to make sure it works. When the window opens, try typing a resident name in the search box. Finder will display not only the log for that person, but every log in which that resident's name is mentioned. Nifty!
- Enjoy.
I'm sure you can do something similar in your OS of choice. I mean, if you're using something other than OS/X it must be because it is better, right?