The alternatives to hourly billing are limited only by your imagination.
Here is an article from Sylvia Hsieh, Lawyers Weekly USA republished at the Missouri Bar Association web site. It lists numerous ways to avoid the current iteration of the hourly billing model.
Be creative! Every client and every matter is different. Make sure your billing model makes sense for your client, and for you.
In one example, a law firm that represented developers decided to calculate its legal fees according to how much it would cost its clients per square foot of property.