#!/bin/sh

key=DateTimeOriginal
if [ "$1" = "-k" ]; then
  shift
  key="$1"
  shift
fi

moncmd="montage -label %f\\n%[EXIF:$key] -geometry 120x120+20+20"

if [ $# -eq 0 ]; then
  echo "usage: thumbindex [-k <EXIF key>] <image file> ..."
  echo "thumbindex generates images containing 25 thumbnails each of the image files given on the command line." | fmt
  exit 0;
fi

pagenr=1

while [ $# -ge 25 ]; do

  for i in 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24; do
    thispage[$i]=$1
    shift
  done

  if [ $pagenr -lt 10 ]; then
    $moncmd "${thispage[@]}" thumbindex0$pagenr.jpg
  else
    $moncmd "${thispage[@]}" thumbindex$pagenr.jpg
  fi
  pagenr=$((pagenr+1))

done

if [ $# -eq 0 ]; then
  exit 0
fi

if [ $pagenr -lt 10 ]; then
  $moncmd "$@" thumbindex0$pagenr.jpg
else
  $moncmd "$@" thumbindex$pagenr.jpg
fi

This script creates thumbnail images containing 25 thumbs each and display the EXIF time and date if your version of ImageMagick supports that (some do not).

Thumbnail table with date/time

date

Bash