Hardware Topics

So in theory it looks like a CMOS sensor allows "random access" to it' s pixels -- which is exactly what I want (I want to pull my images from the sensor using non-standard scanning patterns, etc).  In reality, it looks like many cmos sensors from aptina, etc providethe video in a few standard scan patterns (progressive, interlaced) -- presumably as a "convenience"
 
++Does anyone know of a CMOS sensor that allows for completely arbitrary, full user programable scan pattern?
++  Some CMOS sensors allow specifying a region on interest or window -- can the windows be changed at fairly high speed (faster than frame rate) -- separately, I have seen a sensor from fairchild semiconductor that allows the frame rate to be increased signficantly as the window size decreases (allowing for essentially constant bandwidth).  I get the sense that this sensor is quite expensive.  I noticed from aptina allows windows of interest but the frame rate stays the same (I think)/  In theory a user controllable window would be ok for my needs assuming it could be as small as 5x5 and jump around arbitrarily at high speeds.  Does anyone know of such a sensor?
 
thanks!