Similarities to Inception
Some people go as far as calling "Inception" a rip off of "Paprika." Whether that is the case or not, I wanted to discuss the similarities that both films share, aside from the premises of them - to be able to enter the dreams of others, using cutting-edge technology, to achieve a certain goal.
Paprika's character is very similar to Ellen Page's and Marion Cotillard's Character in Inception. She knows how to make "shortcuts" through different dreams, and can strategically inject herself into people and places in dreams.
The idea of being able to "share" dreams.
In Paprika, it is possible to cast doubt in the mind of a dreamer to alter their perception of a subject, although that is lightly touched upon. It becomes the whole premise of inception.
Dreaming within a dream.
No one knows where a dream ends and reality begins. In fact, there is a theory that the entirety of Inception is a dream (because of its ending).
Details which tell the dreamer that they are actually dreaming, and not believing in the dream "reality" they are in (ie. the Totems in inception).
Can anyone think of any more?