[asdefghyk]

It is also quite useful to know exactly which alarm triggered. It would seem it is not feasible to have a DIY system to implement this

[gregmac]

Regular interlinked alarms don't really allow this, since if one triggers they all alert.

You could potentially do this with "smart" alarms, or a traditional alarm system like DSC with each detector on its own zone (the main alarm siren sounds rather than all the individual units). I'm not sure how or if this complies with current building codes though, which I believe require an audible alarm in every bedroom (which normally means an interlinked unit in every room).

[doubleg72]

I didn't click the link yet, but one could easily DIY with a microcontroller at each alarm, picking up the alarm signal in some fashion or another.