A poisonous one...
In all seriousness, it does look a tiny bit like the Brown Recluse, but I thought they lived more in wild areas. I saw one that looked a lot like that in my house last year. Could be something scary, could be something harmless.
Arachnophobia, or even just a dislike of spiders is one of the most common human fears. It's probably a natural evolution hang on instinct telling us to be careful and play nice with species like those. But spiders themselves are VERY passive, and there is no real reason to be afraid. Millions of other ways that people are more likely to die than a spider bite.
I know that doesn't help much... but I've found it to be true.