Glyn Clough has a nice solution for exporting xsltlistviewwebpart
Update 2014-09-19
I have found another way to easily export any web part from a SharePoint page, without needing to update web part properties:
Here is the most important text from the blog post:
In SharePoint there is a hidden application page that exports web parts: /_vti_bin/exportwp.aspx
. This page takes two query parameters:
pageurl
. The absolute url of the page where the web part resides that you want to export
guidstring
. The guid that is called webpartid in the markup on the page
So, suppose, you have this site: https://intranet.contoso.com and a web part (id: 0c3adfe9-8f5d-4432-918a-42410e4e324d
) on a page https://intranet.contoso.com/Pages/default.aspx
This will be the resulting URL to export your webpart:
https://intranet.contoso.com/_vti_bin/exportwp.aspx?pageurl=https://intranet.contoso.com/Pages/default.aspx&guidstring=0c3adfe9-8f5d-4432-918a-42410e4e324d
Paste it into the web browser address bar and you'll download an xml file with your web part definition. This method works in SharePoint 2010 and SharePoint 2013 and even in SharePoint Online (Office 365).