Yes, I'd second you on that!

You also have various other options in the iButton range; eg, you can write information onto the DS1991 - so you could, say, program certain keys with certain privileges or restrictions, without having to maintain a central database.

Or you could record info onto the key - perhaps for working hours, or entitlement to "free" goodies from the vending machine,...

the possibilities are endless!

Try the 'Search' here - there's been a few discussions before.