I really like those questions! They seem more thought out than most of the stock interview questions a google search will show you. I definitely stopped as soon as I was asked for an email though. There's no way I'll give you my valuable email space just to see some interview questions.
I'm currently not charging for my service, so I decided that asking for an email address was fair. I was torn about how many questions to give "for free." I started with 9, but went down to 6 since I don't think interviewees have enough time to ask more than 2-5 questions in an interview any way.
Fair enough though. I'm also very stingy with my email address. Thanks for the feedback!
