An excellant way to keep your clothes nice and soft after a wash:
1\2 cup of vinegar per clothing load for the rinse part of a washing cycle
It’s very simple, and there are no environmentally hazardous chemicals involved. Your clothes come out softer than with the synthetic stuff. You’ll find it easier to iron your clothes, too! Best thing is that Vinegar is an everyday, household chemical.
Warning: Don’t use vinegar when you’re using bleach. This causes toxic fumes to be released.
A little more on Vinegar: http://en.wikipedia.org/wiki/Vinegar