nappies, nappies, nappies

I seem to have spent an inordinate amount of time lately thinking, reading and sadly even dreaming about nappies. Its all about wanting to make an informed choice but realising that doing that is not always straight forward. Intuitively, I'm not really keen on disposable nappies. But the name of the game is of course lessening the environmental impact. So, I want to be sure that the environmental impact of cloth nappies is significantly lower than disposables before I put us through the pain of using them - with all the washing and drying etc.
And, of course, all disposable and all cloth nappies are not the same. I'm sure this would have been a much easier comparison if cloth nappies were still just squares of cotton cloth that you fold up and pin on, but these days there's 'modern cloth nappies' that don't need folding or pins but can have all kinds of things in them apart from cotton like bamboo and hemp and microfibre and special waterproof coverings - all of which have their own kind chain of (poorly documented) environmental impact.
After wading through limited research results and pseudo information from all kinds of cloth nappy advocate groups etc (Oh yeah, turns out there's legions of people obsessed with nappies, eek, is this what motherhood does to you?), it seems to boil down to cloth nappies will have a smaller environmental impact but only if you wash them in large loads with a relatively efficient washing machine, don't use a tumble drier, or use them on more than one kid. This is basically because cotton uses massive amount of water and pesticides so the production part is really high impact. This part of the impact can be reduced if you get hemp or organic bamboo ones (but non-organic bamboo uses loads of chemicals in the processing which has a huge impact as well).
Or, to really reduce the impact, you could buy second hand-ones, the attractiveness of which might be tempered depending on how you feel about cloth that has already caught some other kids poo (I'm still undecided).
My personal favourite idea, from a website full of patterns and instructions to make your own nappies (where do these people get the time?!!), is the old t-shirt nappy. Totally recycled, easy and free (depending on how many old t-shirts you have).