Our Beta chapter has kinda made a tradition out of throwing a foam party every spring. There are a variety of rental companies that will ship you the machine, you're responsible for setup and damages, then you ship it back to them. We rented two machines, shipping and return included for a little under 800 dollars. There are tons of rental companies, just search google. As far as the whole slippery foam part, we had a drunk girl crack her head on the concrete where the party was. The next year we decided to look into wet foam alternatives and found out that they sell "non-slip" foam, which looks and feels exactly like wet foam, only it isn't soapy and people don't slip and fall, well not as often...
