Oracle Database Discussions

Is there an oracle utility that one can use to automate export of oracle table data into a text file(*.txt) in a format readable by other window applications. I have seen examples using sql plus but I need some thing that can be scheduled to run late at night or early in the morning. I dont want to manually create the file everyday. If there is no utility is there a way to run sql plus in a windows batch file to create such an output.
Thanks
Bunmiog