1. It's fascinating.
2. It's intriguing.
3. I couldn't tear myself away.
4. I couldn't put it down. (this phrase is used for en extremely interesting book)
5. I was so into it, I lost track of time.
6. It does nothing for me.
7. I was bored to tears.
8. I was bored to death.
9. I was dying of boredom.
10. It's about as exciting as watching paint dry. (= it's very boring)

History Facts
Before modern plumbing, a gong scourer was a boy who was sent into cess pits to scoop and scrape all the muck into buckets and remove it. The job was so horrible it was done at night so that people wouldn't have to see it happening.      .. More >>