Here is a fantastic project that a Bangkok, Thailand based non-profit organization is engaged in. Siam Soundtrek is working to preserve the heritage sites of Old Bangkok. To draw awareness they have established a Google Maps mashup on their website and samples of their Mp3 tour through the heart of the old city can be downloaded right from the map! Visitors to the mashup can download the tours for free as well as edit information on their wiki. This tour can act as an on or offline way to explore one of South East Asia's most vibrant city!
Other Google Maps mashups and viewing tools for Thailand: