You give the script the four letter identifier after sprunge.us/ and an optional filename( if noone is given it defaults to the letter identifier), and it downloads it. Utilizes AES decryption with static key for imrpoved privacy for personal files

sprunge_get

#!/bin/bash
decrypt="openssl enc -aes-256-cbc -base64 -d -k $key"
url="sprunge.us/$1"
file="$(curl $url | $decrypt)"
if [ "${file:0:9}" == "Filename:" ]; then
        echo Filename found
        firstline=$(echo "$file" | head -1)
        filename=${firstline:9} 
        content=$(echo "$file" | tail -n +2)
        echo "$content" > $filename
        echo "Saved to $filename"
else
        if [ -z $2 ]; then
                filename=$1
        else
                filename=$2
        fi
        echo $file > $filename
        echo "Saved to $filename"
        
fi

more quotes, less subprocesses

untested, but should work

#!/usr/bin/env bash

key='your key here'
decrypt="openssl enc -aes-256-cbc -base64 -d -k $key"
url="sprunge.us/$1"

mapfile file < <(curl -s "$url" | "$decrypt")

firstline="${file[0]}"
if [[ "${firstline:0:9}" == "Filename:" ]]; then
    echo 'Filename found'
    filename="${firstline:9}"
    printf '%s\n' "${file[@]:1}" > "$filename"
    echo "Saved to $filename"
else
    if [[ -z "$2" ]]; then
        filename="$1"
    else
        filename="$2"
    fi
    printf '%s\n' "${file[@]}" > "$filename"
    echo "Saved to $filename"
fi