While all too often it’s easy to label the internet and MP3 technology as the death of music as we know it, in fact there are many sites which are helping people discover music in new and interesting ways. Today someone brought to my attention the BBC’s Sound Index, which crawls some of the most popular music sites such as Last.fm and MySpace to work out an aggregated measure of what the hottest music on the web is right now.

As just that it’s an interesting index of what’s out there (as I type, Coldplay are the biggest thing right now) and a very nice coverflow interface, but the really smart thing is the “my index” feature, which allows you to build your own charts according to what you like and what people of the same age and country you are in also like – here’s one I made earlier, to use a famous BBC catchphrase.

Overall it’s a really neat and easy to use tool, and interesting how they have managed to build up a partnership with all the relevant sites. Give it a mobile interface for music lovers on the go, and the ability to buy downloads, and you could have the beginnings of a really really useful service.