Found this little spider in the bath this morning. Its bodylength was only about 6mm, but it could run fast on its stripey legs. We identified it as Harpactea hombergi, a nocturnal hunter common throughout UK, especially the southern half. I took these shots on a piece of white paper, using the MP-E65 and MT-24EX with simple homemade diffusers.
This is a head-on two-shot focus stack:



