Retain Twitter Bootstrap Collapse state on Page refresh/Navigation

You can very easily solve this by a cookie. There is a lot of simplified libraries, like https://github.com/carhartl/jquery-cookie as I use in the example below :

<script src="https://raw.github.com/carhartl/jquery-cookie/master/jquery.cookie.js"></script>

add the following code to a script section (#accordion2 refers to the modfied twitter bootstrap example, I list afterwards)

$(document).ready(function() {
    var last=$.cookie('activeAccordionGroup');
    if (last!=null) {
        //remove default collapse settings
        $("#accordion2 .collapse").removeClass('in');
        //show the last visible group
        $("#"+last).collapse("show");
    }
});

//when a group is shown, save it as the active accordion group
$("#accordion2").bind('shown', function() {
    var active=$("#accordion2 .in").attr('id');
    $.cookie('activeAccordionGroup', active)
});

And you are done! Here a modified version of the example at http://twitter.github.com/bootstrap/javascript.html#collapse with clickable links, when you go back – the last shown accordion group opens up automatically

<div class="accordion" id="accordion2">
  <div class="accordion-group">
    <div class="accordion-heading">
      <a class="accordion-toggle" data-toggle="collapse" data-parent="#accordion2" href="#collapseOne">
        Collapsible Group Item #1
      </a>
    </div>
    <div id="collapseOne" class="accordion-body collapse in">
      <div class="accordion-inner">
        Link : <a href="http://google.com">google.com</a>
      </div>
    </div>
  </div>
  <div class="accordion-group">
    <div class="accordion-heading">
      <a class="accordion-toggle" data-toggle="collapse" data-parent="#accordion2" href="#collapseTwo">
        Collapsible Group Item #2
      </a>
    </div>
    <div id="collapseTwo" class="accordion-body collapse">
      <div class="accordion-inner">
        Link : <a href="http://stackoverflow.com">stackoverflow.com</a>
      </div>
    </div>
  </div>
  <div class="accordion-group">
    <div class="accordion-heading">
      <a class="accordion-toggle" data-toggle="collapse" data-parent="#accordion2" href="#collapseThree">
        Collapsible Group Item #3
      </a>
    </div>
    <div id="collapseThree" class="accordion-body collapse">
      <div class="accordion-inner">
        Link : <a href="http://cryptozoologynews.blogspot.com/">cryptozoology news</a>
      </div>
    </div>
  </div>
</div>