I made a double batch of homemade laundry detergent yesterday and it occurred to me that I have not yet posted the recipe here... I've been making my own detergent using this recipe for nearly 2 years and love it--it's cost effective, eco-friendly, easy to make, and it works--I have no reason to go back to store bought detergents. I don't remember where I found this recipe originally, but there are lots of different versions out there if you search around a bit, including recipes for liquid detergent too.
1 bar of soap, grated finely (Most recipes call for Fels Naptha bar soap. I tend to use this one because it works well on stains although there are other soaps out there that or more eco-friendly and less fragrant. I generally grate most of it and leave just a little left over so that I can spot treat stains before I put them into the washer.)
1 Cup Washing Soda (I buy it at Bashas, for those of you in AZ)
1/2 Cup Borax
Mix well. Use 1-2 Tablespoons per load.