[yogesch]

In principle, this is a good idea. But look carefully and you'll notice that in most developed markets, there's just too many index funds, and too many indices. You can find all kinds of specialized indices - most of which may actually be unsuitable for you.

If you read earlier advice from Buffet/Graham, they talk about being long term optimistic about the overall US economy. So if you really want a good passive way of doing things, just stick to the major market indices, like nasdaq100, snp100, etc. Be sure that the index you pick is liquid enough.

On a more practical note, talk to a financial advisor, at least initially, if you're inexperienced/untrained in this stuff.