This is a method of manifestation in a dream that I call the cartoon method. What you do is simply reach into your pockets with the intent of pulling out the object you want. If I remember correctly I tried this in my lucid dream last night and had my first successful manifestation throughout the period of eight lucid dreams (sure I've manifested things but not what I wanted at the time.)
I think that manifestation techniques such as this one may be useful for changing scenes, making characters, and using dream powers as well if you're having a difficulty with them, however the manifestation of objects that do things, which you should be able to do without them would only be a stepping stone for your confidence before you can do it without a dream machine of some sort.