A Long Legged Sac Spider (Cheiracanthium sp.) I found in my basement. A lot less menacing than it looks, probably only 3/4 of an inch including legs. These are very very common spiders in the house, no doubt you have a few around too. This is a male, you can tell by the large black furry palps. You can see a photo of a female here. The male seems to have much longer legs and a wider carapace.
Several reports classify these spiders as possibly harmful, but real study shows their bites are not poisonous or necrotic to humans.
Raynox DCR-150 mounted on my Panasonic Lumix FZ8. I used a simple styrafoam bowl as a flash diffuser for the lighting. Worked out very well if you ask me.