Here's a nice one:

A census taker knocks on a man's door and asks if he has children.
"I have three children" the man says.
The census taker then asks: "How old are they?"
The man, being a keen mathematician replies: "The product of their ages is 72, and the sum of their ages is the same as my door number"
"Don't be ridiculous" says the census taker, "I can't figure out their ages from that"
"Oh right" replies the man "I forgot to mention that my eldest daughter likes chocolate"

The census taker then writes down the ages of the tree children.

How old are the three children, and why?

Riddle: there are the dead bodies of Romeo and Juliett on the floor, on the floor there are also: a water pud, glass shards, (belonging to some kind of glass pot before it broke) and some kind of little rock.
The window is open, but no one got inside of the room in 3 days before R&J were killed.
How did they die?