Title

This module, in a basic sense, allows the title to be an actual Drupal field. This comes in especially handy when doing translations, as titles are not translatable in core.

Translation Management Tool

The description on the module's project page sums this up: "The Translation Management Tool (TMGMT) module provides a tool set for translating content from different sources. The translation can be done by people or translation services of all kinds. It builds on and uses existing language tools and data structures in Drupal and can be used in automated workflow scenarios.

Hermes

A distribution which is a central server for managing translation jobs.

MuseScore: open source music project translated into 30 languages

Earlier this morning, I was watching a DrupalCon video about MuseScore. Buried in the middle of the presentation is a talk about how it is being translated into 30 languages with the help of the community. Well, I don't have time now to research all the translation modules that were used, but I at least wanted to list them here for reference: