Thanks for the info. I'm interested in what features rikaichan is offering. I'll check it out.
I just finished something similar, rikai on a browser toolbar. It's at our website Nipponster (at the bottom right), if you want to play with it.
It has:
-Rikai (just enter the site url into the search box and click rikai)
-a funtion that let's you use the Jim Breen Japanese Dictionary from anywhere on the web
-live Japanese internet radio and tv broadcasts
-Japanese language audio lessons/ language lesson radio station
-Metropolis magazine podcasts (updates about what is happening in Tokyo every week)
-flash cards for kana and over 2,000 kanji
-and a function to search our new Japan-related search engine, Nipponster