IF you Know PHP and have experience to setup secure login access with ability to "Warn both admin and user if someone else start using user account" then this project is yours
you will provide full description before expecting to communicate if you understand the idea then we can go ahead I will judge you from the way you will describe how you will code/setup that or "if you have ready example and you provide as demo"
Here is more info:-
1- You login to our site daily from your own home pc/laptop/work pc... and certain country IP address.
2- You enabled advanced security protection option for your account.
3-we will ask you to setup "secure access word"|| "PC name we store" || "secret question " ||Optional mobile #" || optional email" and option to lock your account in case suspicious access made.
4- System log will be at Google analytic or other logging service
5- Now the system will have intelligent to " know if you changed your PC || if you logged in with double accounts || if someone using your account from different IP/PC/MAC etc.." then system will take action " will log that info for you and for admin ,,, system will take action to enforce answering some of your security options you setup in order to access your account
6 - other idea for to improve such access control system will be great