Weird behavior can vary widely depending on context and cultural norms, but here are some examples:

1. Talking to oneself in public.
2. Wearing mismatched or unconventional clothing.
3. Collecting unusual items, like toenail clippings or expired food.
4. Extreme obsession with a niche hobby or interest.
5. Frequent and intense mood swings.
6. Eating non-food items, known as pica.
7. Believing in and discussing conspiracy theories.
8. Engaging in bizarre rituals or superstitions.
9. Inappropriate public displays of affection.
10. Persistent and extreme paranoia.

Remember that what’s considered weird behavior can be subjective, and it’s important to approach people with understanding and empathy rather than judgment.