Check out this cool new open source browser (and tagger, and favorites manager, and search results manager, and blog poster) called Flock. It's still in development, but you can download a beta version and play around with it. You can do a bunch of things with it (at least thirteen different things)...I uploaded this blog post using it, for example*.
* OK, actually it didn't work quite as I thought -- it gave me an error message and I had to come here to blogger to actually publish the post. Maybe that's a bug they'll get fixed in later versions???