#!/bin/bash

for f in `ls -p | grep -v /`; do
    file="$f"
    modtime=`stat --format=%Y "$file"`
    year=`date --date @$modtime +%Y`

    if [ ! -d "$year" ]; then
        mkdir -p "$year"
    fi

    echo "Moving $file to $year..."
    mv "$file" "$year/"
done