For jQuery hash support I like the jQuery Address plugin: http://www.asual.com/jquery/address/ . Especially, if you want to make a form or product filter, you can use this variant: http://www.asual.com/jquery/address/samples/form/ .
Though, it doesn’t support checkboxes in the form of arrays like check[]=1&check[]=2 , etc. I updated the plugin with some other libraries and code and now it works.
You can download it here.