As far as I know, indoor GPS on patenting ideas GPS repeaters
has not moved. However, someone promises
that SiRFstar V technology SiRFusion by the end of 2012 will work in the premises. But such promises are heard for a couple of years, and working chip is not...
As for Wi-Fi, the options are many:
is perhaps the most known commercial Wi-Fi system.
— Fraunhofer Institute.
(Wi-Fi + GPS + GSM) is quite old (2005), the Intel prototype, open source.
Note that to get any decent accuracy Wi-Fi system should be periodically calibrated, since the signal strength over time, floats, and positioning accuracy decreases.
accuracy to 15 cm, but not Wi-Fi (requires additional iron) and costs about 10-20 euros. If money is not a problem, it is, in my opinion, the best option.
There is still GloPos
that based on GSM data promise an accuracy better than 12.5 m But "independent tests" that they reference is not really confirmed.
Positioning system based on FM radio does not require infrastructure receivers is already in the bunch of mobile devices, but the commercial FM systems has not yet matured...