There are 2 previous versions of this script.
// ==UserScript==
// @name gmailCoordinates
// @namespace http://www.geekyneighbor.com/
// @description Adds "Get Coordinates" link to Google Maps
// @include http://maps.google.com/*
// ==/UserScript==
//window.addEventListener("load", function(){setTimeout(Main,200);}, false) ;
window.addEventListener("load", function () {
var bar = document.getElementById("topbar-startcol");
bar = bar.getElementsByTagName("ul");
bar = bar[0];
// Create and insert Spacer
var spacerText = document.createElement("li");
spacerText.innerHTML = ' <img src="http://maps.gstatic.com/intl/en_us/mapfiles/transparent.png" class="panel-bar-divider bar-divider"> ';
bar.insertBefore(spacerText, bar.firstChild);
var showLinkContainer = document.createElement("li");
var showLink = document.createElement("a");
// Embed javascript functionality (rather than bookmarklet)
showLink.setAttribute("href", "javascript:void(prompt('Center Coordinates',gApplication.getMap().getCenter()));");
showLink.setAttribute("id", "c_launch");
var showLinkTextSpan = document.createElement("span");
var showLinkText = document.createTextNode("Get Coordinates");
showLinkTextSpan.appendChild(showLinkText);
showLinkTextSpan.setAttribute("class", "link-text");
showLink.appendChild(showLinkTextSpan);
showLinkContainer.appendChild(showLink);
bar.insertBefore(showLinkContainer, bar.firstChild);
}, false) ;