Watch the Space Slide online guitar lesson by Jeff McErlain from Guitar Effects Survival Guide
Here is a cool sounding trick that I have used many times and people really dig it when you pull this one out. I stole this from one of my favorite players, David Gilmour and I first saw him use the slide as a bow in the Pink Floyd Live at Pompeii film. Gilmour uses it to create some very cool ambient spooky guitar sounds that can clearly be heard on the Echoes studio recording. I highly recommend the Live in Pompeii film if you are a guitar fan. Of course Jimmy Page used a real violin bow to get a similar effect, and looked the coolest ever doing it!