Toggles elements by their title as characters are typed into the text box.

Refactored.js

// The character array as a queue was clever but poorly implemented and unnecessary.
// Instead, just read the query from the input.
// Also handles mouse driven content actions (cut, paste, etc).

$(function() {
  var filter = function(query) {
    var titlesSelector = "#content .show h3 a";
    if (query == '') {
      $(titlesSelector).closest(".show").show(); 
    } else {
      $("#content .show").closest(".show").hide();
      $(titlesSelector + ":contains('" + query + "')").closest(".show").show();
    }
  }
  var h = function(eventData) {
    filter($(this).val().toLowerCase());
  }; 
  $("<input>", {
    "placeholder" : "type to filter by title",
    class: "search",
    keyup: h, 
    focusout: h, 
    mouseleave: h
  }).appendTo("#content h4");
}

ToggleElementsOnScreen.js

// assumes that the title content is lowercase.
// I'm aware of the duplication of some functionality. 
// this is just a POC for the work I'm doing on ccs. :)

var titlesSelector = "#content .show h3 a";

$(function() {
  var characters = new Array();
  $("<input>", {
    "placeholder" : "type to filter by title",
    class: "search",
    keyup: function(eventData) {
      if (eventData.keyCode == 8) {
        characters.pop();
      }
      pattern = characters.join("");
      showSelector = titlesSelector + ":contains('" + pattern + "')";
      hideSelector = titlesSelector + ":not(:contains('" + pattern +"'))";
      $(showSelector).parent().parent().show();
      $(hideSelector).parent().parent().hide();
    },
    keypress: function(eventData) {
      var newChar = String.fromCharCode(eventData.which).toLowerCase();
      characters.push(newChar);
      pattern = characters.join("");
      showSelector = titlesSelector + ":contains('" + pattern +"')";
      hideSelector = titlesSelector + ":not(:contains('" + pattern +"'))";
      $(showSelector).parent().parent().show();
      $(hideSelector).parent().parent().hide();
    }
  }).appendTo("#content h4");
}

Rather than both showing the positive matches AND hiding the negative matches, I think it might be more efficient to hide them all and then show the positive matches. Also, I'd suggest using the literal [] rather than new Array() -- literals are always a safer bet than the initialization equivalents because they actually have quirky differences.

@thegrubbsian even better(?) the code is up live at http://chicagocodecamp.com.