I'm running Ubuntu as my main OS. inside that, running VMware with Windows XP Pro. in windows I'm running Vmoo which I have logging everything. If I weren't so attached to Vmoo, I'd just drop it and run it all through linux apps.
back linux side, I run terminal windows with:
$ tail sindome_log.txt -f | grep "whatever that window will look for and display"
Protip: you can "tail filename.ext -n #"
where "#" is the number of lines back you would like to start from.
in the case of the screenshot, I'm GREPing "|C|" and "OOC-Chat". but you can grep whatever, so things like "http://" for a list of all the links from OOC-Chat, or you can egrep -i '=>|<=' for a window of only private SIC messages (and xtra sense condom SICADs)
in Vmoo, I use triggers to hide the lines that I'm GREPing elsewhere.
for lines of text I'm not hiding and viewing elsewhere, I use triggers to color code the screen for key texts such as: "you", "your", "to you", "you see", "There is", "There are"...etc --this allows me to try and keep up in a crowed room or for other reasons, keep up when I have a lot on my screen to take in.
I don't use triggers to perform commands or actions in the game except for one to which Johnny says "meh". aside from that, triggers are forbidden, so make sure you're not doing anything that's against the rules when customizing your game.
it *does* get a little confusing with too many windows open, though. you don't know which one to look at, or you forget to check one. and then you gotta remember which window is which. but for most general players with characters that aren't infomaniacs, a setup similar to the screenshot is usually good enough.