Arduino max current

from all pins combined

200mA is the maximum of all the combined pins, no one pin to exceed 40mA
These are absolute maximum ratings.
The data sheet says:-

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

The 5v rail if driven from the USB then with a 500mA limit less that that.
If driven from the on board regulator then it depends on what the input voltage is, the limit is given by the power dissipation of the regulator and is discussed here:-
http://www.thebox.myzen.co.uk/Tutorial/Power_Examples.html