This Tampermonkey script allows you to hide Facebook posts based on their content.

// ==UserScript==
// @name         Facebook Sanity
// @description  hide facebook posts containing sepecific words / phrases
// @match        *facebook.com*
// @require      http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js
// ==/UserScript==
myContainer(document.body);
document.body.addEventListener('DOMNodeInserted', function(event) {
    myContainer();
}, false);
// The reason for using a function like this is to call this script again
// during subsequent AJAX requests by Facebook
function myContainer() {
    // if adding or removing, follow the format below, some characters need
    // to be preceded by backslashes, definitely ellipses
    var myList=["Occupy Monsanto","Im here to offend \(18+\)",
                 "StreetArt in Germany", "Fascinating Places",
                 "Illuminati Exposed Media", "The Peoples Boycott"];
    for (var i = 0; i < myList.length; i++) {
        // entirely remove the post
        //$("li:contains("+myList[i]+")").css("display", "none");
        // replace the post with text saying that it was deleted
        $("li:contains("+myList[i]+")").html("deleted");
    }
}

Update: This does seem to result in a performance hit.