Hey,
It has been a really long time since I have actually used Hindi for writing anything. I have kind of forgotten the script also. Neither do I know typing in Hindi.
The other day, Mrigank sent me the address of Quilpad and I was toying around with it for some time. It is the newer page that I was looking at. There were some widgets allowing you to do native language search, but I felt that it was missing the distribution that it warrants. Hence I picked up my tools, and here it is, the first version of GreaseMonkey transliteration.
On any page, any textbox, you doulbe click it, and a div opens in the bottom right. As you type words in English, sounding like Hindi, you get the Hindi script. It seems to working great with things like Yahoo mail, Orkut, Meebo, Gmail, Digg, and others. Please do let me know if it fails on sites.
I am also working with Anshuman to get our own transliteration service, and convert this to plugin. The current script is a little slow as I was too lazy to extract words and transliterate them; right now, i am doing it for the whole value of the text box !!
I think I would be working on all these issues, and releasing it by tomorrow (too wishful !!! )
Here is the location at UserScripts
http://userscripts.org/scripts/show/9473
