I really don't think there is a fool-proof method for this but of course I'm coming here for advice...
I have a project that I want to restrict to 3 uses per day per user based on IP address. Of course I can do this easily with a mysql table for traditional use cases...but how would I account for those clever enough to use something like foxyproxy (a proxy switcher plugin for firefox) and/or open a new browser to get a new session. Every use would appear as a fresh, unique user.
Am I stuck to a non-fool-proof method or is there anything else I can try? I am pretty certain that most of our user base will not have a clue how to use or even what these methods are but I want to account for it anyway.
EDIT: If there is a non-php solution to this as well, I am open to any ideas.