This is a very cool hack using which you can find a person on orkut (in case he or she is on orkut) using his or her e-mail address.
» About
» Instructions
- Navigate to the orkut invite page – http://www.orkut.com/Invite.aspx
- Enter the email address, fill captcha and click on submit.
- If that person is on orkut, you will get link to his or her profile with an option to add as friend
» Credits
Dheeraj informed us about this hack over at Orkut Plus Community
Gaurav Dua – Orkut Guru – 535 Points 
22, Webmaster and Businessman. Based in Jammu, J&K – India
Gaurav has written 503 Articles, posted 322 Comments.
