My mother found this little "friend" behind a set of drawers. We think it is a Black Widow, however it isn't round like a female black widow, it might be a male but the pictures of those don't seem to quite match either.
The scale is tenths of an inch, so 0.5 is half an inch, and 0.4 is about a centimeter.
That said, I would lean toward the brown widow. The leg coloring better matches that than the black widow. The black widows I have seen around Boise Idaho when we lived there were all black except for the hourglass.
Looks like an adolescent black widow to me. Black widows don't get fully black until full maturity, with their legs usually being the last to change. Either way, kill it and look around for others and also an egg-sac, then use a long bbq lighter to burn the sac.
