I just released an inital Beta of IP 2 Locale. I'd love to hear any feedback you may have...
Drupal is set up fairly well for multilingual sites. However, it does make the assumption that each site version will be written in a different language. It is quite feasible however, that there be two versions of a site in the same language. For example, A site which has a UK version, and a version for the Republic of Ireland. Both sites are written in English, but the content varies for each. Drupal's multilingual features provide the perfect tools to allow 'translation' of content from one version of the site to another, but In a setup like this, it may also be desirable to automatically redirect users to a particular version of the site based on their IP address. Drupal's built in Language negotiation does not cater for this...
IP 2 Locale is able to redirect users to a specific site version based on the originating country of their IP address. It can use one or more IP lookup modules to translate the users IP address into a country code. Mappings can then be provided from country code to language code, and these mappings will be used to determine which version of the site to redirect to. Redirections can be configured to happen for the initial page request of a 'session' only (where 'session' is, a user coming from external site), or for every single page request.
IP to Locale currently supports IP to Country lookup by one or more the following modules: