The eventorganiser_get_currencies() function used in Event Organiser Pro to return details of the support currencies (human-readable name, symbol, HTML symbol).

currencies.php

<?php
/**
 * Returns an array of available currencies.
 *
 * Applies the filter 'eventorganiser_currencies'. Returns an array of the form
 *
 *      currency identifier => array(
 *                              'name' => currency name,
 *                              'symbol' => currency symbol,
 *                              'symbol_html' => symbol in html
 *                             )
 *
 * @since 1.0
 * @uses filter eventorganiser_currencies to allow currencies to be added/removed/altered
 * @return array An array of available currencies
 */
function eventorganiser_get_currencies() {
	$currencies =  array(
		'USD' => array('name'=>'USD - U.S. Dollars', 'symbol'=>'$','symbol_html'=>'$'),
		'GBP' => array('name'=>'GBP - British Pounds', 'symbol'=>'£','symbol_html'=>'&pound;'),
		'EUR' => array('name'=>'EUR - Euros', 'symbol'=>'€','symbol_html'=>'&euro;'),
		'AUD' => array('name'=>'AUD - Australian Dollars', 'symbol'=>'$','symbol_html'=>'$'),
		'BRL' => array('name'=>'BRL - Brazilian Real', 'symbol'=>'R$','symbol_html'=>'R$'),
		'CAD' => array('name'=>'CAD - Canadian Dollars', 'symbol'=>'$','symbol_html'=>'$'),
		'CZK' => array('name'=>'CZK - Czech koruny', 'symbol'=>'Kč','symbol_html'=>''),
		'DKK' => array('name'=>'DKK - Danish Kroner', 'symbol'=>'kr','symbol_html'=>'kr'),
		'HKD' => array('name'=>'HKD - Hong Kong Dollars', 'symbol'=>'$','symbol_html'=>'$'),
		'HUF' => array('name'=>'HUF - Hungarian Forints', 'symbol'=>'Ft','symbol_html'=>'Ft'),
		'ILS' => array('name'=>'ILS - Israeli Shekels', 'symbol'=>'₪','symbol_html'=>'&#8362;'),
		'JPY' => array('name'=>'JPY - Japanese Yen', 'symbol'=>'¥','symbol_html'=>'&#165;'),
		'MYR' => array('name'=>'MYR - Malaysian Ringgits', 'symbol'=>'RM','symbol_html'=>'RM'),
		'MXN' => array('name'=>'MXN - Mexican Pesos', 'symbol'=>'$','symbol_html'=>'$'),
		'NZD' => array('name'=>'NZD - New Zealand Dollars', 'symbol'=>'$','symbol_html'=>'$'),
		'NOK' => array('name'=>'NOK - Norwegian Kroner', 'symbol'=>'kr','symbol_html'=>'kr'),
		'PHP' => array('name'=>'PHP - Philippine Pesos', 'symbol'=>'Php','symbol_html'=>'Php'),
		'PLN' => array('name'=>'PLN - Polish zloty', 'symbol'=>'zł','symbol_html'=>''),
		'SGD' => array('name'=>'SGD - Singapore Dollars', 'symbol'=>'$','symbol_html'=>'$'),
		'SEK' => array('name'=>'SEK - Swedish Kronor', 'symbol'=>'kr','symbol_html'=>'kr'),
		'CHF' => array('name'=>'CHF - Swiss Francs', 'symbol'=>'CHF','symbol_html'=>'CHF'),
		'TWD' => array('name'=>'TWD - Taiwan New Dollars', 'symbol'=>'$','symbol_html'=>'$'),
		'THB' => array('name'=>'THB - Thai Baht', 'symbol'=>'฿','symbol_html'=>' &#3647;'),
		'TRY' => array('name'=>'TRY - Turkish Liras', 'symbol'=>'TL','symbol_html'=>' &#3647;'),
	);
	return apply_filters( 'eventorganiser_currencies', $currencies );
}