Amanuens is the easiest way to manage software localization. By connecting directly to your source code repository, it allows translators to work directly in their web browser. Amanuens can be configured to automatically synchronize with your repository, notifying translators of changed/new items to translate. The system can also commit changes, so you don't have to do anything manually. Last but not least, you can either use your own translators, or just purchase translations directly from the integrated human-powered service.
Software by Threeplicatewww.threeplicate.com