(Check also the page on links, where there are other sites with excelent articles.)

• From Sleep Consciousness to Pure Consciousness, by Jayne Gackenback
• Also, from Jayne Gackenback's site, more articles on Higher States of Consciousness
• See the list of articles from the Astral Society
• Lucid-Dreaming: Awake in your sleep? by Susan Blackmore
• From the Lucidity-Institute:Other Worlds: Out-of-Body Experiences & Lucid-dreams
• Also, from the Lucididy-Institute: article on Sleep and Cognition: Lucid-Dreaming: Psychological Studies on Consciousness During REM Sleep
• Dreams and Meditation by Campbell Kaiser
• An article on Dream Recall
• In Your Dreams, by Mirian Harline
• Anything is Possible in Lucid-Dreams, by Virginia Lew & Douglas Wise
• Robert Bruce has writen two more parts of his exceptional Treatise on Astral Projection. However, as far as I know, you will have to write him an email and ask for the zipped file to be sent directly to you.
• Finally, here is an account of a Kundalini type experience, by Metta Zetty: Epiphany: Gift of Light - A Spontaneous Experience of Awakening into Awareness