I found this one on the garden bench but I've also found a few in my greenhouse. It was about 4cms long and 2cms wide😮
Duke
(http://i255.photobucket.com/albums/hh131/jazzbyrd/f3c23c8be1c6fcc8eb44bc23f489754a_zpslaqarczt.jpg)
I believe it could be an Eyed hawk moth, in a "i'm trying to sleep" mood. Try gently opening the wing span and take another photo...