I've been exploring alternate realities and encountering spirits and entities for years now. I've encountered good and bad. I can vouch for the fact that whenever trying to get rid of bad spirits, using the name of Jesus really does work. I don't know if it's the only thing that works.
These things usually happen to me when I'm dreaming, or in the state between dreaming and waking. Here's one story in particular that I think applies: One night I woke up and I could feel a vibrating energy all over my body. This is called the "vibration stage" that precedes astral projection. As I drifted into a dream, I found myself transported to the upper floor of some house. There was a spirit there - someone in his upper teens or low 20's had committed suicide there by hanging himself off the top of the stairs.
Then the spirit started to come after me. I don't know if "attack" is the right word for it, because there wasn't anger or hostility behind it, but more like a "poor me, feel sorry for me, feel my pain" kind of thing. I could feel a tightness around my neck. He kept lunging at me. Finally I decided I'd had enough, and that there wasn't anything I could do to help him, so I said "In the name of Jesus Christ, I command you to leave now." Then I saw two angels come in holding a bar between them, and they used it to sweep the spirit away. I also sensed Jesus kind of in the distance, watching.
I thought Great, this is a good opportunity to have a little chat, so I told Jesus that I was his servant, and that I would do anything he asked of me. He said "You don't have to call on me. If you could only see how powerful you are on your own."
I think that's the one thing a lot of people are missing. The whole point of his message was that EVERYONE can do what he did, and more. We all have it within ourselves - the same thing he found. It's not about relying on some external source. Although that works, that's only the first step. The next step is finding the same thing within yourself. As Jesus said "The kingdom of Heaven is within you." Eventually we will move beyond calling on Jesus' name to deal with negative spirits - we will use our own power.