When I started weaning my son, I thought I would try these angled bottles to help him to learn to feed himself eventually.
They are made at an angle and you can buy handles for them too to make it easier for your baby to feed him/herself without breaking their necks to drink from a bottle.
They work fairly well too. It makes life a lot easier to feed my son in his highchair as he doesn't need to be tilted right back and ,with the handles, he could learn to feed himself( if he ever wants to!!)
The rim and the handles (available separately) and made of the Baby Basics soft plastic and the bottle is easy to handle.
The only problem I have found is that they can leak a bit easily, they have markers so you know how much to loosen the lid to let the air in easier but there isn't much of a thread on the lid and it can leak if you're not careful.
A very good concept though.