Here are five popular modern pseudosciences:
1. **Homeopathy**: The practice of using highly diluted substances to treat ailments, based on the principle that "like cures like," despite lacking scientific support.
2. **Astrology**: The belief that the positions and movements of celestial bodies can influence human behavior and events on Earth.
3. **Crystal Healing**: The practice of using crystals and gemstones for therapeutic purposes, claiming they can promote healing and balance energy.
4. **Alternative Cancer Treatments**: Various non-evidence-based treatments marketed as cures for cancer, often bypassing conventional medical approaches.
5. **Flat Earth Theory**: The belief that the Earth is flat, countering the well-established scientific understanding of the Earth's shape and gravity.