I use Tumblr's sharing bookmarklet a lot (http://www.tumblr.com/goodies). This opens up a popup window with basically the following url:
http://www.tumblr.com/share?v=3&u=<current page url>&t=<current page title>
However I almost always change a few things (use the queue instead of posting right away and set a specific tag).
Does anyone know if the share URL accepts extra parameters? That way I could make one bookmark that tags the post with "x" and queues it, and another that invokes the usual behavior. I can't find a useful documentation.