Seriously one of the best Photoshop finds this year. If you use photoshop effectively, you need this.
“Dealing with grids in Photoshop is a pain
With GuideGuide, it doesn’t have to be. Pixel accurate columns, rows, midpoints, and baselines can be created based on your document or selection with the click of a button. Frequently used guide sets can be saved for repeat use. Grids can use multiple types of measurements. Honestly, if you haven’t started downloading it by now, you’re probably a masochist. Weirdo…”