Translation tools are devised in such a way that not only they help you in speedy translation, but they help you in maintaining consistency across your work and with find & replace tool if you want to correct your common errors. They also provide machine assisted auto-translation features that help you translating strings as much as 30 to 40 % automatically depending upon your available translation database. Some tools are platform specific and some are available cross platform.

Here is the review of some of them available to you as a translator:

http://raviratlami1.blogspot.com/2006/07/tips-for-linux-localization.html