My Grandmother and Gramdfathers best friend (let's call him Jack) had passed away. He was always the kinda guy who would prank people. We all knew him well as he was a family friend and when he passed away, strange things starting happening.
The phone rang and my father answered it and all it said was "Hello, it's jack" and then hung up - I do realise this just could be a prank call by the way.
Then one day I was out with my Grandparents in town, and when we got home their whole furniture was rearranged! Not messy, just in different places, and absolutely nothing stolen. To this day we still get the odd weird thing happening!