This is a Data Logger and Recorder built for trainning purposes using previous experiences with Arduino and Processing. Still has some minor problems; but I'll leave it like that for now as my time is very limited and I'm kind of tired by now.
Input signal is connected directly (no amplification) to any of the Arduino analog inputs. User can select input channel from the computer screen.
here are the details: http://www.adrianelectronics.com/index.php?p=1_43_Data-Logger-Recorder
here is the video: https://www.youtube.com/watch?v=oTthPJNIToE