I like details, and I like to maximize stuff and so on. I want Google pagespeed to give me best possible speed scores (even for logged in users).
One of the relatively few things it's still complaining about is a few non-optimized images of this module:
Losslessly compressing x/sites/all/modules/contrib/admin/images/sprite.png could save 2.9KiB (48% reduction). See optimized version.
Losslessly compressing x/sites/all/modules/contrib/admin/images/black.png could save 654B (70% reduction). See optimized version.
Thats like 3500 bytes we could save, or 28 000 bits! A potential half of a second lost for those still running dial ups (0.00001%), or 0.01 seconds for 99% people on the first page load! My god!
Pagespeed provides the losslessly optimized images, and I have them attached here for your convenience, If you would like to fix this travesty.