years ago I came home late from working in a hotel on april 1st and changed all the clocks in the house so that when everyone thought they'd had a lie in, it was stil drastically early. I even woke them fiddling with the clock and said I was doing "nuthin" and they went back to sleep.
In the morning I enjoyed my stubborn dad saying I hadn't changed the clocks. He rang the speaking clock 4 times and my uncle before he believed me, bah humbug!
This year I told my husband I won a grand on the national lottery but hadn't the heart to keep it up. He was so sweet I felt guilty as hell.
But fawhk do I love practical jokes! One guy blew up the toilets in his school with chemicals one april fools.