Gimp Script: Grid of Guides
One of the things that bugs me about Gimp is that if you change the grid size you have to restart gimp for the change to happen. This is a pain when working on a dungeon map where I like to snap to grids for convenience sake.
I found a handy script at the Gimp plugin registry to create a grid of guides. The original script allowed you to specify how many guidelines you wanted in the X and Y direction. I posted a modification to allow an option to specify the pixel spacing instead of the number of lines.
I am attaching the modified script here as a convenience.
Here is the GUI (you access it from Image>Guides>Grid):
And a the resulting guides:
I find this much faster to use than setting the grid.
(Edit: and to remove then use Image>Guides>Remove all Guides)