Last night one of these flew in through our open living room window. It is a green lacewing (Neuroptera: Chrysopidae), probably what used to be called Chrysoperla carnea, but this species has recently been shown to be a group of very similar-looking species which can only be reliably distinguished on the basis of their songs (see here and here for details), so I suppose I should identify it as Chrysoperla sp.
Photos taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2009-09-05.
While looking at the Chrysoperla carnea page at Jim Lindsey's Ecology of Commanster site, I realized that, earlier in the day, I had taken a photo of something that looked very like a C. carnea larva. It was hunting on a yarrow (Achillea millefolium) flower head.
At the time I took these two photos I assumed that it must be some sort of beetle larva, but the colour and pattern match those of C. carnea rather well. A tentative identification, I think.
Photos taken in Reading, UK, on 2009-09-05.