i have noticed certain sites which allows limited hit per IP so can i programatically make them feel that requests are not coming from the same IP ,
well i am not
Firstly, I'd hope that any sites which are trying to do source throttling aren't going to trust some arbitrary header. The packet says where the response has to go back to - I'd hope that they'd throttle based on that.
Secondly, if a site doesn't want you to hit them repeatedly, don't you think it's rude of you to try to circumvent that? If I were a site owner and I noticed someone trying to do that, I'd probably blanket ban them if at all possible.