Which? the consumer rights group, has an excellent baby section. Amongst the latest research are the most useful and the most useless baby products parents advocate. Amongst them baby carrier, baby sling, bumbo seat and nappy stacker.
Actually, I have to say that most of the most useless items are actually quite important in our household. the nappy stacker is brilliant if you use reuseable, washable nappies to tidy them up all in one place, but I agree that if you use disposables nobody would find the time taking these out of the plastic bags and putting them into a nappy stacker jut because it looks a little bit tidier.
I am still finding the Bumbo seat brilliant for my little one to learn to sit upright and train his muscles and play in it.. Babies only seem to use it for a very short time though but I find it invaluable for that very short time.
And the door bouncer he just loves but I am just starting to use it now in between learning to sit and walk at 8 months. The fabric sling has the big disadvantage that you just need to spend time on learning how to use it, and then my little one does not like to ave his legs spread apart for sitting on my back, The baby carrier Baby Bjoern is very good and gives us real close- and cuddleness and the little one the feeling of being safe and secure, he never cries in it when we go out, as we loosely do the attachment parenting.
My pram however was the most useless item so far, as it did not fold so the baby could lie flat securely and now that he is sitting up he is unable to properly sit in it either but slides around to such an extent that I fear his back gets damaged if I use it.
As the little one sleeps in our bed the cot and the sleeping bags have been pretty useless so far, too. Advantage though is that we always have a good night sleep for at least 8- 10 hours daily, and in my opinion its more natural for the babies to sleep cuddled up with us.
The baby feeding essentials, like freezer trays, are also pretty useless in our household as we do the baby-led weaning.