Bookmarklet to generate deterministic passwords based on a service name

generate-pass.html

<p>Minified and ready to be dragged to bookmarks toolbar<br />
Remember to customize the 4 parameters at the end</p>
<a href="javascript:(function(c,f,g,e){var a=location.hostname.split('.');do var b=a.pop();while(a.length&&3>=b.length);this._custom_?b=prompt('Write the service name',b):this._custom_=!0;var a=b,d;for(d in e)a=a.replace(new RegExp(d,'i'),e[d]);a=a.replace(/[a-z]/,function(a){return a.toUpperCase()});a=f+a;a+=g.slice(-(c-a.length));a=a.slice(0,c);alert('Service:'+b+'\nPassword:'+a)})(10,'Gp','_T8e.P2j!',{i:'!',a:'@',s:'$',l:1,z:2,e:3,g:6,t:7,b:8,o:0});">
Generate Pass  
</a>

<p>Uncompressed source code</p>
<pre>
(function(length, prefix, suffix, map) {
	/* 1.0 */
	var p = location.hostname.split('.');
	// Find service name
	do { var service = p.pop(); }
	while (p.length && service.length <= 3);
	// First time assume domain
	if (!this._custom_) {
		this._custom_ = true;
	} else {
	// If clicked again let them fill the name themselves
		service = prompt('Write the service name', service);
	}
	var pass = service;
	// Replace characters, only once per character
	for (var c in map) {
		pass = pass.replace(new RegExp(c, 'i'), map[c]);
	}
	// Upper case first lower case char
	pass = pass.replace(/[a-z]/, function(c) { return c.toUpperCase(); });
	// Add prefix
	pass = prefix + pass;
	// Fill with suffix chars up to desired length
	var diff = length - pass.length;
	pass += suffix.slice(-diff);
	// Crop to desired maximum length
	pass = pass.slice(0, length);
	alert('Service:'+service+'\nPassword:' + pass);

// NOTE: Change these values to customize your pass
})(10, 'Gp', '_T8e.P2j!', {
	i: '!',
	a: '@',
	s: '$',
	l: 1,
	z: 2,
	e: 3,
	g: 6,
	t: 7,
	b: 8,
	o: 0
});
</pre>