This FLASH game Pet Society by Playfish had people addicted for hours. Its market is mostly girls, from toddlers to the elderly, sucking in poor hapless fathers and boyfriends to play with their loved ones.
The peak was when hackers were enjoying and teaching some adventurous gamers how to cheat for more paw points and get more coins and clone items.
Best and pioneer hacker was from youtube user cyrus513 who invented the cloning method, and paw point hack. This was soon too proliferated and Playfish patched everything by March 2009.