Since the previous script is for an isometric wall, the obvious choice for the next script would be one to automatically generate a wall. I'd written one previously, but this seems as good a time as any to post it!
This script will generate a brick wall with mortar. The wall and mortar can each be any color. The height and width of the bricks, as well as the mortar thickness can also be picked. There are color variations in each brick that you can set manually (the amount that the R, G, B values of each individual will deviate from the "standard" brick color.) The final wall is then bump mapped onto some noise to give it some texture.
The script is under the "/Filters/SambrookJM/" menu in GIMP, although that can be changed by editing the last line of the script to put it wherever you want it to go.
 A few more changes to the script. You can now set the layer mode for the bricks, in case want it to be Overlay, normal, or anything of the other possible modes. The tile size and saturation for the cubism filter used on the mortar can be set. Finally, the "Bevel and Emboss" portion of the layer effects scripts are now included in this script.
[edit #2] I think I fixed the Linux problem. It happened with a (rand 4000000000) statement, which Linux doesn't like (even though Windows does. Go figure...) I changed that, so hopefully this should work on Linux and Windows machines alike.
[edit #3] Fixed an error where the color variation was set to zero giving a divide by zero error. Now that is fixed. Thanks for gerard82 for being a far more diligent tester than I was. :-)