yea, countless times. Usually spontaneously, but if i'm in a lucid dream and sit down and meditate, i'll go there. I've also dosed psychedelics and/or alien drugs I can't identify more times than i can remember in dreams. The affects are always way more bizarre than when dosed here.. The only way to sum it up is that its like not only you dosed the drug, but the world around you took the drug as well. Theres no seperation between the other dimensions and the normal reality
One of the interesting things to me is that (like ringworm said) a lot of the times when i wake up during the middle of one of these dream-trips there is full fledged psychedelic affects that quickly fade off