cocojambo - 8:49 pm on Mar 21, 2012 (gmt 0)
Yes there was an Adsense in my City (well 3 hours away from me) back in February, but I did not attend.
The traffic surge came from 1) Google ranked me #1 for a keyword. 2) Bing.com ranked me top 3 for one keyword but it only generated a high amount of traffic for one day, and the next it slowed down.
Guess what? I gathered all IP, referrer, city/state and computer logs for this day (Wednesday March 14th). I sent it over to them. I did not see any invalid activity.