Pony.fm/app/library/Gravatar.php

<?php

	use Illuminate\Support\Facades\Config;
	use Illuminate\Support\Facades\URL;

	class Gravatar {
		public static function getUrl($email, $size = 80, $default = null, $rating = 'g') {
			$url = 'https://www.gravatar.com/avatar/';
			$url .= md5( strtolower( trim( $email ) ) );
			$url .= "?s=$size&r=$rating";

			if ($default != null)
				$url .= "&d=" . $default;
			else {
				$size = 'normal';
				if ($size == 50)
					$size = 'thumbnail';
				else if ($size == 100)
					$size = 'small';

				$url .= "&d=" . urlencode(URL::to('/images/icons/profile_' . $size . '.png'));
			}

			return $url;
		}
	}