Cheapest way to buy rubber mulch?

Question:I need to fill in a playground area, and want to use rubber mulch but it is so expensive. Is there a cheaper way to get it?

Answers:
You can buy it in bulk. They deliver it in big 1 ton sacks. The cost will depend on how close you live to a supplier, but they are pretty easy to find on Google, I've even seen them listed on ebay.