Boost WordPress performance: Faster localization, (on the fly) dynamic image resizing and CDN support for images.
MO-Dynamic benchmark: Comparing front page of a "fresh" WordPress 3.8.1 installation with active apc cache using different configurations. As you can see, using MO-Dynamic with active caching is just as fast as not translating the blog or using native gettext. Benchmarked version 0.6, times are mean of four test runs measured using XDebug.
Settings, simple view (v1.6)
Localization settings, advanced view (v1.6)
Image settings and debugging, advanced view (v1.6)
Debug Bar integration (v1.0)