Contrary to popular belief,you can throw your own foam party, using common household materials.
What is a Foam Party?
Foam parties are becoming popular at some clubs. You step onto the dance floor, and it's covered with four feet of soap foam. It doesn’t take too much imagination to see that this has the potential to be quite a bit of fun. You don't need an expensive machine to do this though---we (a bunch of MIT students) did it our own basement---here is a photo essay.
Following the instructions herein could easily destroy your house. You and you alone are responsible for any damage you cause. These instructions do not constitute a guarantee that if you follow them, your house, your health, your morals, or whatever will not be damaged or destroyed. Don't say we didn't warn you, and above all, don't bring a lawsuit against us. If you don't have the permission of the owner of the building, you shouldn't do this!
Selecting a Venue
Foam is a mixture of soap, air, and water. When you dance in foam, it turns back into soap, air, and water. No matter how carefully you cover the walls and floor of the room you do this in with plastic, some water is going to get onto the walls and floor. If you do this in a room with a hardwood floor and plaster walls, you are going to destroy the room. The ideal place to this would be outside on a driveway during a hot summer day. But, if you want some winter fun, you can also do it inside, in a concrete-floored basement with concrete or cheap wood-panel walls. Again, if you don't have the permission of the owner of the building, don't do this!
Preparing the Venue
First, cover the walls and floor with plastic sheeting. The plastic should be heavy-gauge. Plastic sheeting sold for use as a painting drop cloth works well. The party area should not be any larger than about 15' by 15'. If it is larger, you can put some folding tables on their sides to barricade off a party area, and cover them with plastic sheeting as well. If your venue is outside, you can surround the entire party area with folding tables.
When the foam starts to "melt," the floor is going to get covered with water. You don't want your guests to slip and hurt themselves. The non-slip stickers for the bottom of a bathtub would be ideal, but if your budget is a bit lower, pieces of old carpet (to be thrown out afterwards) also work.
Gather the following:
Put the kiddie pool on the floor inside the party area. Place the trash can inside the kiddie pool, face up. Place the shop vac outside of the party area, and run the hose to the inside of the trash can. Run the hot-water hose so that the nozzle is inside the trash can. Put the joy bottles next to trash can.
Put on the shop goggles. The goggles are to protect your eyes from the foam as it sprays from the trash can. Get some mops ready to clean up the mess if you screw up.
Turn on the shop vac, and turn on the hot-water hose. Hold the shop-vac nozzle and the hot-water hose nozzle together about halfway inside the trash can. Water should spray out of the trash can and into the kiddie pool. Adjust the water pressure at the faucet until water is coming out of the hose at exactly the same rate as the shop vac is blowing water out of the bucket. You should be at a "steady-state"; the trash can may have some water in the bottom fourth or so, but it should be filling up. If any water is splashing onto the floor (and not into the kiddie pool) lower the shop-vac nozzle and hot-water hose nozzles further into the trash can.
Now, start squirting the soap at the nozzle of the hot-water hose. Foam will starting building up in the bucket and start pouring all over the place.
Eventually, the kiddie pool will fill up with water. Two people should be in charge of emptying the kiddie pool with buckets into a drain. (A sump pump might also work for this if you have one around)
Foam Accumulation Tips
You may need to have an assistant spread the foam out with a snow shovels. Also, since dancing rapidly destroys foam, you'll need to have someone making foam throughout the party.
Try your hand at making foam before the day of the party! You don't want your guests to show up and be disappointed! Do a small-scale test ahead of time! Testing is also a good time to try out variations to the procedure outlined here. If you find any improvements to the procedure, and especially if you find some other kind of soap that works well, let me know. (I suspect Mr. Bubble might be a good choice.)
Lots of people are going to come to your party, because foam is a big novelty. Make sure you make very clear on the posters what will be going on---a phrase that worked for us is "they will actually fill their house with foam." It's probably a good idea to set up a changing area for your guests, so they can put on swimsuits or old clothes or whatever community standards dictate. It's also probably a good idea to provide towels for them when they exit.
Make sure you have good music, and everything else you would normally have at a party. Above all, don't kill anyone! Make sure you are aware of the additional risks that foam and water bring to your party, and take precautions.