Not much going on here, just a few implementations, uses and comments:

C++ code:

static const char gif1x1t[] = "\

file identifies this as: GIF image data, version 89a, 1 x 1

identify (from ImageMagick) identifies this as: GIF 1x1 1x1+0+0 PseudoClass 2c 8-bit 44b

Neither these or other programs seem to have an issue if the last "\x00" is left off... but I left it in here as that is what GIMP put in the file -- and I figure GIMP knows best