See a working example of the site: http://www.allourideas.org/studentgovernment
Some possible project ideas include:
Right now the All Our Ideas is available in English, Spanish, French, Portuguese, and Arabic. However, we have had users create idea marketplaces with ideas in Hebrew, Dutch, German, Chinese, and Basque. In order to make All Our Ideas available to people all over the world, we would like to integrate our site with the Google Translate API which would make the site available in 57 languages.
There are many places where the design and user experience in All Our Ideas can be improved. We'd like someone to work on making the site even more beautiful and easy to use. With our stream of traffic and A/B testing infrastructure, the designer should get quantifiable feedback on the effect of these changes.
Photocracy.org (photos+democracy=photocracy) is a sister project of All Our Ideas that allows groups to collect and prioritize photos. We would like to have a widget which people could use to embed a photocracy into their website. An All Our Ideas widget was a project of one of our summer of code students last year (more information), and that widget has already been used by many groups including the Washington Post, the Craigslist Foundation, the Princeton University Student Government.
Skills you might need, depending on the idea