Is there a way to see which pixels are what coordinates with crosshairs on iPhone simulator?

I just use the built-in screenshot snapper from OS X. Just Command+Shift+4 and when you drag it shows the dimensions of the snap you'd take. Press escape to drop it. Works great.

In the Developer Tools -> Applications -> Graphics Tools there is a program called Pixie. It will do what you want. In Preferences you can set it up so that an option-drag will count pixels. You can also set it to just show the pixel coordinates and do the math yourself.

I've used the Iconfactory's xScope for this before. If you create rulers that are the size of the display in the Simulator, you can get a readout of the X and Y coordinates of the mouse pointer as you move across the Simulator screen. Getting the rulers precisely aligned with the edge of the Simulator screen can be a little tricky for applications with dark backgrounds, though.