Car Lock Control System (help needed!)

Hey guys!
i am currently making a car lock system
its requirements are as follows:

> it should have two switches; lock/unlock
> when u press unlock, it should unlock only for 30sec
> when it is in locked state, and someone tries to open the door, the alarm should be turned on
> the alarm should also last only 30sec if it is triggered

i have made the switches using 555 timer IC
and unlock only activates for 30sec

but i am open to ideas regarding this, i think i can do this in so many ways!

so all i want from you guys is to give me some ideas to make it innovative
and please suggest some other ways of doing it too!

thanks

This application cries out for a micro controller. It can easily handle all the timing and sensing needs. It can also support a keyless entry.

I would suggest looking in to a manufactured car alarm, Viper (DEI) products will do what you need.