Then, add a new menu item like this:
rxvt -fn fixed +sb -geometry 80x40 -e w3m -cookie %a(w3m,Enter URL to open:)
And that's it! The URL is entered in the dialog box, and replaces the %a(...) sequence in the command above. The URL needs to be fully formed, of course. Perfect for reading a journal entry, or a quick news article.
Oh, there's a side benefit. When entering data into textareas, w3m
brings up $EDITOR. So I can now enter journal entries using