Not that it would help anyone - but the hidden code is the number, that one of the Math professors at my university used in his lectures, to mean "a vary large number". He was teaching both of my parents so the number dates to some rather old times. The number was called "Minakov's Constant" by his students. I don't think you can Google it.
Here is a hint that may help you: by now I only received a test message at this new email address, never anything else.
Solution: the hidden code = 1275642
New Email: firstname.lastname@example.org
My favorite tools are Firebug and Outwit. I learned about them at Sourcecon in 2011 and over the past year they have been priceless. I found the solution by using firebug to analyze the source code of Irina's profile page on the Ning network. I opened firebug and searched for "hidden" and there it was!
I thought I might be able to use this process to find the new email address too, but no luck, so I checked Irina's profile pages on all the networks. Again, no luck so I moved on to searching Google, combining "Irina Shamaeva" and various keywords.
This gave me pages on http://booleanstrings.com/ (Note: I was not able to access the site due to server errors yesterday so I opened the cached page instead) The certification link on the page sent me to the new site: sourcingcertification.com. Links to previous contests also gave me a number of Irina's new domains.
I used "Whois" to verify that Irina was the owner of the domains and check for a new email there, but her primary email was listed. I also ran site searches on each of the new domains looking for emails.
Ultimately, I guessed that Irina would use the same structure on her new email as she did on her existing email (FirstName@Domain.com), so I sent the email to email@example.com & firstname.lastname@example.org.
Although Irina didn't get the email right away when I sent it, I also sent her a note on LinkedIn and gave her my guesses. Just like real recruiting - try multiple methods of communication until something is successful!
Thanks for the contest Irina - it was fun to exercise my sourcing muscles :-)
Congratulations. I will definitely check out Firebug and Outwit. I copied the source code into Word and used the FIND option to look for the word 'Hidden". It works but I didn't think to look on Irina's page!! As you rightly say, some of the magic is in the technology and some is just good old-fashioned brain power. I think Glen Cathey calls it Human-Computer Information Retrieval.
Enjoy the course.
Out of curiosity how did you know to inspect a source code for the answer?