How to use "besides" in a sentence

Most of his friends had shared his avid interest in ghosts and ghouls; besides, the grotesque hadn't been his only interest, so she had decided not to worry about it.

Now you're talking about another power besides telekinesis."

To Tina, Elliot said, "What else will we need besides thermal clothing, boots, and snowshoes?"

And besides ...' he looked at me