Something you should know: If you are using Windows 7 and get double accents when typing, you might have a serious problem, because it seems like this is a side effect of any activated keyloggers. While it’s nice that these cannot be active entirely unnoticed, it is annoying if you use a program that you want to log your keyboard actions.
In my case, the text expander FastFox was acting as a desired keylogger to supply shortcuts while I typed.