Recursive random file

random_file

#!/bin/bash
dir="directory" # no slash at end
files=$(ls -R $dir | awk '
/:$/&&f{s=$0;f=0}
/:$/&&!f{sub(/:$/,"");s=$0;f=1;next}
NF&&f{ print s"/"$0 }');

list=();
while read -r line; do
  list[${#list[@]}]=$line;
done <<< "$files"

file="${list[RANDOM % ${#list[@]}]}"
while [[ -d $file ]]; do
  file="${list[RANDOM % ${#list[@]}]}"
done;
kde-open "./$file"