This script will calculate the total price of everything on the Steam UK store. Designed to be run from the PHP CLI. Requires cURL.

total-steam-price.php

<?php
header('Content-Type: text/plain');
$total = 0;
$id = 0;
$apps = array();
set_time_limit(0);

// Get a list of all valid apps
$applist = file_get_contents('http://api.steampowered.com/ISteamApps/GetAppList/v2');
$applist = json_decode($applist);

foreach ($applist->applist->apps as $app)
{
	if (is_int($app->appid))
	{
		$apps[$app->appid] = $app->name;
	}
}

unset($applist);

krsort($apps);

echo "Last ID\tProgress\tTotal Price\tPHP Memory\tPeak Memory\n";

$curl = curl_init();
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);

foreach($apps as $id => $name)
{
	$ids = (string)$id;
	
	try
	{
		curl_setopt($curl, CURLOPT_URL, 'http://store.steampowered.com/api/appdetails/?cc=uk&appids=' . $id);
		$data = curl_exec($curl);
		$json = json_decode($data);
		if (isset($json->$ids->data->price_overview->final) === true)
		{
			$price = (int)$json->$ids->data->price_overview->final;
			$total = $total + $price;
		}
	}
	catch (Exception $e) {}
	
	$progress = array_search($id, array_keys($apps)) . '/' . count($apps);
	
	echo str_repeat(' ', 80) . "\r";
	echo $ids . "\t" . $progress . "\t" . number_format($total/100, 2) . ' GBP' . "\t" . number_format(intval(memory_get_usage()/1024)) . 'Kb' . "\t\t" . number_format(intval(memory_get_peak_usage()/1024)) . 'Kb' . "\r";
	
	gc_collect_cycles();
}