gravatar.js

function gravatar(email, options) {
	// using md5() from here: http://www.myersdaily.org/joseph/javascript/md5-text.html
	function md5cycle(e,t){var n=e[0],r=e[1],i=e[2],s=e[3];n=ff(n,r,i,s,t[0],7,-680876936);s=ff(s,n,r,i,t[1],12,-389564586);i=ff(i,s,n,r,t[2],17,606105819);r=ff(r,i,s,n,t[3],22,-1044525330);n=ff(n,r,i,s,t[4],7,-176418897);s=ff(s,n,r,i,t[5],12,1200080426);i=ff(i,s,n,r,t[6],17,-1473231341);r=ff(r,i,s,n,t[7],22,-45705983);n=ff(n,r,i,s,t[8],7,1770035416);s=ff(s,n,r,i,t[9],12,-1958414417);i=ff(i,s,n,r,t[10],17,-42063);r=ff(r,i,s,n,t[11],22,-1990404162);n=ff(n,r,i,s,t[12],7,1804603682);s=ff(s,n,r,i,t[13],12,-40341101);i=ff(i,s,n,r,t[14],17,-1502002290);r=ff(r,i,s,n,t[15],22,1236535329);n=gg(n,r,i,s,t[1],5,-165796510);s=gg(s,n,r,i,t[6],9,-1069501632);i=gg(i,s,n,r,t[11],14,643717713);r=gg(r,i,s,n,t[0],20,-373897302);n=gg(n,r,i,s,t[5],5,-701558691);s=gg(s,n,r,i,t[10],9,38016083);i=gg(i,s,n,r,t[15],14,-660478335);r=gg(r,i,s,n,t[4],20,-405537848);n=gg(n,r,i,s,t[9],5,568446438);s=gg(s,n,r,i,t[14],9,-1019803690);i=gg(i,s,n,r,t[3],14,-187363961);r=gg(r,i,s,n,t[8],20,1163531501);n=gg(n,r,i,s,t[13],5,-1444681467);s=gg(s,n,r,i,t[2],9,-51403784);i=gg(i,s,n,r,t[7],14,1735328473);r=gg(r,i,s,n,t[12],20,-1926607734);n=hh(n,r,i,s,t[5],4,-378558);s=hh(s,n,r,i,t[8],11,-2022574463);i=hh(i,s,n,r,t[11],16,1839030562);r=hh(r,i,s,n,t[14],23,-35309556);n=hh(n,r,i,s,t[1],4,-1530992060);s=hh(s,n,r,i,t[4],11,1272893353);i=hh(i,s,n,r,t[7],16,-155497632);r=hh(r,i,s,n,t[10],23,-1094730640);n=hh(n,r,i,s,t[13],4,681279174);s=hh(s,n,r,i,t[0],11,-358537222);i=hh(i,s,n,r,t[3],16,-722521979);r=hh(r,i,s,n,t[6],23,76029189);n=hh(n,r,i,s,t[9],4,-640364487);s=hh(s,n,r,i,t[12],11,-421815835);i=hh(i,s,n,r,t[15],16,530742520);r=hh(r,i,s,n,t[2],23,-995338651);n=ii(n,r,i,s,t[0],6,-198630844);s=ii(s,n,r,i,t[7],10,1126891415);i=ii(i,s,n,r,t[14],15,-1416354905);r=ii(r,i,s,n,t[5],21,-57434055);n=ii(n,r,i,s,t[12],6,1700485571);s=ii(s,n,r,i,t[3],10,-1894986606);i=ii(i,s,n,r,t[10],15,-1051523);r=ii(r,i,s,n,t[1],21,-2054922799);n=ii(n,r,i,s,t[8],6,1873313359);s=ii(s,n,r,i,t[15],10,-30611744);i=ii(i,s,n,r,t[6],15,-1560198380);r=ii(r,i,s,n,t[13],21,1309151649);n=ii(n,r,i,s,t[4],6,-145523070);s=ii(s,n,r,i,t[11],10,-1120210379);i=ii(i,s,n,r,t[2],15,718787259);r=ii(r,i,s,n,t[9],21,-343485551);e[0]=add32(n,e[0]);e[1]=add32(r,e[1]);e[2]=add32(i,e[2]);e[3]=add32(s,e[3])}function cmn(e,t,n,r,i,s){t=add32(add32(t,e),add32(r,s));return add32(t<<i|t>>>32-i,n)}function ff(e,t,n,r,i,s,o){return cmn(t&n|~t&r,e,t,i,s,o)}function gg(e,t,n,r,i,s,o){return cmn(t&r|n&~r,e,t,i,s,o)}function hh(e,t,n,r,i,s,o){return cmn(t^n^r,e,t,i,s,o)}function ii(e,t,n,r,i,s,o){return cmn(n^(t|~r),e,t,i,s,o)}function md51(e){txt="";var t=e.length,n=[1732584193,-271733879,-1732584194,271733878],r;for(r=64;r<=e.length;r+=64){md5cycle(n,md5blk(e.substring(r-64,r)))}e=e.substring(r-64);var i=[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];for(r=0;r<e.length;r++)i[r>>2]|=e.charCodeAt(r)<<(r%4<<3);i[r>>2]|=128<<(r%4<<3);if(r>55){md5cycle(n,i);for(r=0;r<16;r++)i[r]=0}i[14]=t*8;md5cycle(n,i);return n}function md5blk(e){var t=[],n;for(n=0;n<64;n+=4){t[n>>2]=e.charCodeAt(n)+(e.charCodeAt(n+1)<<8)+(e.charCodeAt(n+2)<<16)+(e.charCodeAt(n+3)<<24)}return t}function rhex(e){var t="",n=0;for(;n<4;n++)t+=hex_chr[e>>n*8+4&15]+hex_chr[e>>n*8&15];return t}function hex(e){for(var t=0;t<e.length;t++)e[t]=rhex(e[t]);return e.join("")}function md5(e){return hex(md51(e))}function add32(e,t){return e+t&4294967295}var hex_chr="0123456789abcdef".split("");if(md5("hello")!="5d41402abc4b2a76b9719d911017c592"){function add32(e,t){var n=(e&65535)+(t&65535),r=(e>>16)+(t>>16)+(n>>16);return r<<16|n&65535}}
	//check to make sure you gave us something
	var options = options || {},
		base,
		params = [];

	//set some defaults, just in case
	options = {
		size: options.size || "50",
		rating: options.rating || "g",
		secure: options.secure || (location.protocol === 'https:'),
		backup: options.backup || ""
	};

	//setup the email address
	email = email.trim().toLowerCase();

	//determine which base to use
	base = options.secure ? 'https://secure.gravatar.com/avatar/' : 'http://www.gravatar.com/avatar/';
	
	//add the params
	if (options.rating) {params.push("r=" + options.rating)};
	if (options.backup) {params.push("d=" + encodeURIComponent(options.backup))};
	if (options.size) {params.push("s=" + options.size)};

	//now throw it all together
	return base + md5(email) + "?" + params.join("&");
}