Ok, it takes a little trick, but it works.
Example:
How-toMake a HTML file like this:
<html>
<head>
<link rel="shortcut icon" href="ps.ico" />
<meta http-equiv="refresh" content="0; url=http://community.projectstealthgame.com/forums/index.php">
</head>
</html>
In this case, I already made the links for you, but you can make it anything you want.
Anyway, save it to some HTML file (I called it psg.htm) and make sure you have a icon called ps.ico (link:
http://myjunk.lennardf1989.com/ps.ico), drop both files somewhere (eg. An directory in your Firefox installation directory) then drag and drop the HTML file onto your bookmark toolbar. The name of the file will be in your toolbar now (in my case psg.htm), so feel free to change that any time.
Now simply click the bookmark a couple of times, and after around 3 times the icon you specified in the HTML file appairs on your toolbar.
---
For the HTML layman's among us
<link rel="shortcut icon" href="ps.ico" /> specifies the icon file you wish to use
<meta http-equiv="refresh" content="0; url=http://community.projectstealthgame.com/forums/index.php"> tells the HTML file to redirect itself to
http://community.projectstealthgame.com/forums/index.php---
I know a JavaScript trick like onload="document.location='<link>'" is possible as well, but not everyone has JavaScript enabled.