webpart titles and properties
templates that MUI doesn't support, such as blogs and workspaces
custom additions to various menus & ribbons
multi-valued columns values
calculated text fields
alert & popup messages
custom new/edit/ etc forms
In addition, it does some translations with less effort than the MUI in many cases. For instance, if you add a custom list and put it in the quick-launch menu, then provide the translation of the list name, the translated list name will not appear in the menu unless you edit it separately. With PointFire, you only have to add the translation in one place. In fact, if the same list name is used elsewhere in a different site, PointFire can inherit that translation from another site.
Of course, translation is only one of the 4 localization techniques that PointFire makes available. There are much more powerful filtering techniques that allow you to tag content in lists, libraries, pages, and webparts as being in one language or the other, allowing SharePoint to assemble the page in the user's language while using the same URL.