Powdered laundry detergent

For the past six months or more I've been making my own laundry detergent.  This whole time I've used only one liquid laundry detergent recipe which calls for castile soap.  After finding myself low on castile soap and high on cheap-skate-miserliness I determined to find a recipe that didn't force me to invest my savings in a new bottle of Dr. Bronner.  I invested $0.94 on a bar of Zote laundry soap.

The recipe I followed goes like this:
1 cup grated Zote soap
1/2 cup washing soda
1/2 cup borax

I found out that a Zote bar grated comes to about 3 cups, so about $0.31 per batch.  I already had the Borax and washing soda, so I don't remember how much those cost, but I know I've been making laundry detergent with them for over six months and the boxes are about half full.  After grating the the Zote I transferred some of the shavings to my chopper to get them into smaller pieces.  Mixed all the ingredients together, and that was it.

I've done several loads of laundry with this and am very impressed.  It only takes about 1-2 tbsp per load of laundry, and things have been coming out smelling fresh, fresh, fresh.  The Zote has a citronella-ish scent.  I will definitely be making this again.