Today I tried Virtaal, the off-line translation tool from Zuza Software Foundation, the same one behind Pootle and translate-toolkit. Virtaal’s user interface is best optimized for keyboard usage than any translation tool I ever used, except maybe for advanced text editors. Thanks to translate-toolkit, Virtaal can edit many translation file formats, not only Gettext message catalogs. The application depends on GTK+ but not on GNOME, and it can be used in UNIX-like operational systems, Windows and Mac OS X.
Virtaal’s user interface is very unobtrusive, but some of its command are not very intuitive. That’s why I suggest reading this introduction before you actually translate something.
The application has some very useful features already. The automatic completion, in example, should avoid typos and increase productivity, and I hope other tools (poEdit, Gtranslator etc.) implement it as well. Spell checking and syntax highlight are there too, even if the syntax support is not as complete as some other implementations. The search is one of my favorite Virtaal features already: it uses a search bar instead of a search dialog, and you can search for a regular expression.
Virtaal lacks many small and large features, so for now it’s just a promising application. I’ll leave it installed, but I don’t have any plans to stop using Gedit + gedit-pomode for free software translation.