If your site uses geo-IP look ups to personalise the site extensively then you might find it tedious having to browse every page in edit mode then select the country/location visitor group you want to test with. I wanted to find a way to make it look like I was browsing from an IP address other than my development machine with a mimum of fuss.
Enter the IIS rewrite module. It is a useful and versatile add on for IIS7.x. Through configuration rules it allows you to modify incoming requests and outgoing responses for your site. One feature that is particularly powerful is the ability to modify incoming header values.
There has been a Geo-IP database lookup function available since EPiServer CMS 6 R2 was released. Recently I wanted to update to the very latest version of the Geo-IP database to ensure a client's site targeted countries as accurately as possible.