I am currently writing my thesis, and for typesetting/layout I use a great free tool called LaTeX. To create the latex files I use a great, nonfree editor called TextMate. It has a great free latex bundle that makes the whole typesetting process an easy and straightforward thing. Today it took me a moment to find out how to change bundle preferences in TextMate.
Those of you who use TextMate's latex bundle are aware of the latex log window, belonging to the Typeset and View command, which displays some information while your latex 
document is being compiled. When everything goes according to plan (i.e. there are no errors in your document) this window is quite useless.
So I disabled the "Keep log window open" option in the latex bundle in order to have the generated PDF displayed right away. A couple of days later I wished this window back, because my latex document had errors. But I couldn't find the config option anymore, because the log window instantly disappeared each time I compiled the document. But here's a little trick to get the log window back: Open the console and copy&paste this command:
defaults write \
com.macromates.textmate \
latexKeepLogWin 1
Now the latex log window should be displayed allowing you to see compile errors and change other settings. I can't imagine this is the only way to do it, though, so if you know how to access this setting once it's been set to 0, let me know :-)
Edit (January 22nd):
The right way to do this would be to open the LaTeX bundle's preference window using the option+command+comma shortcut :-) *bummer*
