We have a great play structure with an angled slide. When it was new (and after the winter months), the kids were getting stuck half-way, defeating the whole purpose of having a slide!
What can you do to make a slide more slippery?
Use a furniture wax (like Pledge), and spray the slide. Wait a minute or so and then wipe it with a paper towel. This is sure to make the slide a lot more fun!
(Just make sure the kids are careful on the first slide, especially if they were getting used to a "slower slide"!)