Progress indicator

It would be great to have some sort of progress indicator to inform the user the the file is being uploaded after clicking submit. It would be ideal if it could show percent remaining. However, a small simple pop-up window with a repeating animated progress bar filling up and a message would be very nice. Something like, "Your audio file is uploading. Please wait until it is finished before navigating away from this page." I think this would prevent users from hitting submit twice or thinking that maybe it isn't working. Thanks for the awesome module!