gistfile1.user.js

// ==UserScript==
// @name           tagSubscribe 
// @namespace      log.kcars
// @include        http://oreno.imouto.org/*
// @include        http://danbooru.donmai.us/*
// @include        http://konachan.com/*
// @include        http://chan.sankakucomplex.com/*
// From https://gist.github.com/Kcars/1291050 adding .user
// ==/UserScript==

var jq = document.createElement("script") ;

jq.src = 'http://jquery.com/src/jquery-latest.js' ;

jq.type = "text/javascript" ;

document.getElementsByTagName("head")[0].appendChild(jq) ;

function loading()
{
	if(typeof unsafeWindow.jQuery == "undefined") 
	{
		window.setTimeout(loading , 100) ; 
	}
	else
	{
		$ = unsafeWindow.jQuery ; 

		start() ;
	}
}

loading() ;

function onClickSubscriber(event)
{

}

function start() 
{
	var host = location.hostname ;

	var feed = "" ;

	if(host.search("oreno") != -1)
	{
		feed = "http://oreno.imouto.org/post/atom?tags=" ;
	}

	if(host.search("danbooru") != -1)
	{
		feed = "http://danbooru.donmai.us/post/atom?tags=" ;
	}

	if(host.search("konachan") != -1)
	{
		feed = "http://http://konachan.com/post/atom?tags=" ;
	}

	if(host.search("sankakucomplex") != -1)
	{
		feed = "http://chan.sankakucomplex.com/post/atom?tags=" ;
	}

	$("#tag-sidebar li").each(function()
	{
		if(host.search("danbooru") != -1)
		{
			var tag = $(this).find("a")[1].textContent ;
		}
		else
		{
			var tag = $(this).find("a")[3].textContent ;
		}

		tag = tag.replace(/[ ]/g , "_") ;
		
		$(this).append("<a href=\"" + feed + tag + "\">" + "RSS" + "</a>") ;
	}) ;
}