Ricoh GR-1
It looks like a point-and-shoot camera because, for all intents and purposes, it is one. But, Ricoh's powerful little brick does a lot more than the typical analog compact. Legendary Japanese street photographer Daido Moriyama used its fast fixed 28mm lens in ways that make it looks so much more logical than a slow, bulky body.

Looking around on eBay, you might be a little surprised to find that the price starts around $300 and can go up from there, but that's because these little things are sought after for their solid mix of image quality and simplicity. It offers full-auto controls, but you can override that with aperture priority mode. It has AF, but it also allows you to lock the focus on a certain distance, including the hyperfocal distance, a must for serious street photographers.

Best of all, it's big enough to feel like a real camera, but small and subtle enough not to draw too much attention.

If you're into the serious point-and-shoot form factor, you can also check out the Contax T2, which goes for about the same price and offers many of the same features. 

Sample Prices:
Ebay: Starting at about $150 up to about $400 for one in great shape.
Craigslist: $200 and up