Susan Warren on "Strange Permalink Alphanumeric Numbers"

Regardless of what I do to the permalink settings I keep getting URL's like this

www.mysite.com//?page_id=6576#.UNfm1a6dhRw

or this

www.mysite.com//cats/cookie/#.UNfm1a6dhRw

with the strange #.UNfm1a6dhRw appended to everything.

The htaccess rewrite rules look like this

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

I've tried it with just a blank htaccess with no rewrite, and I've tried deactivating all the plugins, but the the alphanumerics still appear. Does anyone know why this is happening?

Thanks....