While looking for a shower-cleaner recipe, I came across this blog, which has several different recipes to try: http://www.frugalupstate.com/crafts-diy/readers-question-homemade-shower-spray-recipe/
This works better than any name-brand spray I've tried:
1/2 C Hydrogen Peroxide
1/2 C Rubbing Alcohol
1/4 tsp Dawn Dish Detergent
2 tsp Jet Dry Turbo Dry
1 1/2 C Water
Spray daily - I wait until I'm all done in the bathroom because there's a very strong alcohol smell.