While some people would say that the iTravl is what I use to write my posts*, I don't really know how well it translates between English and the eight languages it supports using its look-Ma-no-hands speech recognition system. Jump for more details and see my nipples explode with delight!
Just for its cheesy, retro sci-fi look, however, I wouldn't care if it translated my "Hello, where can I have a pizza, please?" to "Take your pants down and take me to your leader!" when I visit Moscow.
In addition to translating your gringo babbling into Chinese, French, German, Italian, Polish, Portuguese, Russian, Spanish out loud (and vice versa), the Ectato's iTravl includes Fodor's guides for 50 cities around the world and audio guides to the most important museums.
* In fact, I use John Cleese's original Spanish-Hungarian-English dictionary: