http://www.phpied.com/form-auto-fill-bookmarklet/
My take on the problem from 2006 :)
Mike, hope your project can pick up an idea or two
I find it crazy that you created that 9 years ago!
FormFiller doesn't currently support auto filling the form with data, but it's definitely something i've considered for the future. I've saved that post and will give it another read when I get around to adding that functionality in.
Cheers, Mike