I have indeed looked into it further. It seems the prices have come down tremendously since I first looked at BLE transceivers a couple of years ago along with a lot of DIY/open source community development.
My concern at the time, and up to you suggesting I take another look was that I didn't want the iBeacons on walls and having to carry around a smart phone all the time. I wanted the opposite but without expensive iPhones or whatever on the wall.
Looking at the nRF51822 right now for the room sensors and still poking around for 'fobs'. TI has some interesting sensortags.
The model I'm suggesting is to use an off-the-shelf fob/tag, similar to what @ziplockk mentioned, as the key chain/fob/bodypiercing/whatever that gets carried around. These all send periodic beacons.
At each point where you care about detecting the presence a 'body' carrying such a beacon, you have a 'station' that consists of a BLE host/client/whatever term du jour is being used (BlueGiga has a couple of usable ones) that, in turn, is connected to a gateway device (ESP8266 is a reasonable choice, but RaspPI, or any other programmable device that can bridge between the BLE world and a LAN will work), which revolves the closeness of the 'presence', possibly comparing with other stations, to determine where, exactly the 'body' is with respect to the stations. The concept is trivial and workable as long as you're prepared to fill in a LOT of gaps in coding/hardware integration. I'm not aware of any affordable off the shelf solutions.
Tom