at the moment I like Babelfish http://babelfish.altavista.com/

Mainly for the fact that you can translate from english to another language, but when you translate it back to english it comes out wrong.

example
English: Peter went to the store for the milk
German: Peter ging zum Speicher für die Milch
Translated back again: Peter went to the memory for the milk


see what I mean? hours of fun.

Ever-popular dictionary.com
Very simple to use, and offers a translator as well.

ut now when I see her sometimes when I'm trying
to sleep, I see her somewhere out on the edge of all this
sprawl of cities and smoke, and it's like she's a
hologram stuck behind my eyes.