LockSniffer
Simple tool for checking how long your Windows session has been logged on during the day. Every time you run the app or unlock your work station, a log row is appended to a file. Similarly, when logging off or locking the machine a row is logged. You can check from the super beautiful UI how long you were present during the day.
Usage
Just build with Visual Studio (or download binaries here). From settings file you can select the location of the log file (if you want to put it to dropbox or something). Add the exe to startup folder of your account and that's it. You can bring up the UI from the tray icon.