Google +1 Bookmarklet

google-plus-one-bookmarklet.js

(function() {
	var a,b;
	a=document.createElement('script');
	a.type='text/javascript';
	a.async=true;
	a.src='https://apis.google.com/js/plusone.js';
	b=document.createElement('div');
	b.id='ward_plusone';
	b.style.position='fixed';
	b.style.top='10px';
	b.style.right='10px';
	b.style.padding='10px';
	b.style.zIndex=99999;
	b.style.background='#FFFFFF';
	b.style.border='1px solid #000000';
	b.innerHTML='<g:plusone></g:plusone>';
	document.body.insertBefore(b, document.body.firstChild);
	document.body.insertBefore(a, document.body.firstChild);
})();

From a blog post.