http://sahityam.net/ is a great website which is meant exclusively for lyrics of Carnatic compositions.
It is wiki-based, meaning that anyone can edit it; so it does not depend on one person to keep it updated.
It presents lyrics and translations in a very simple and readable format; the translations appear next to each line of the Sahitya, which makes it very easy to comprehend the meaning of every line of a composition.
Check this page to see how it works:
http://sahityam.net/wiki/Mahaganapatim_manasa_smarami
At the end of each page, there is even a link to downloadable renditions of the composition on that page!
I am sure that sahityam.net has the potential to become a very powerful source of reference for artists and rasikas alike. From the few pages I have seen, there seems to be an emphasis on the correctness of the lyrics as well; the community of the site's users are probably providing good QA.
Great open-source resource overall!