For my MacBookPro, I used some of Norman Koren's gamma test images from here:
http://www.normankoren.com/makingfineprints1A.htmlscroll down to the "Gamma and Black Level chart" section. See attached screenshot for the gamma image I used.
In Photoshop, I made a neutral gray 8bit image the EXACT size (pixel dimensions) of my desktop. I pasted the UNSCALED gamma image from the above link into the document along the left edge of the document. You cannot scale the gamma image or it will cause artifact in the line pattern used to assess display gamma.
I saved the image in PS and made it my desktop image. I can then tilt my display until the gamma reads 2.2 from my particular viewing angle. It does not cure the issues with viewing angle for these displays, but at least you can be somewhat consistent when viewing your display.
Kirk