We used piles of pillows to contain dd at that age. It didn't last long, though. We had to keep adding more pillows to make the wall taller. About the time she could move the pillows around, she was able to learn to get down feet first. She does that off the couch and chairs daily, but I guess because she has fallen from the bed a few times she doesn't even try to get off the bed anymore. We still use the pillows when she's napping so she won't roll off in her sleep.
I don't remember where I saw a product I think it was called Humanity or something . . . it was like a big roll that could be laid along the edge of the bed. With design features to prevent it from rolling off. Might have been from someone advertising at MDC. Anyone know what I'm talking about?
One thing I've larned from this is that every arrangement -- sleeping, childproofing, diaper changing, feeding station -- is temporary. They just grow soooooo fast, the problems change as fast as you solve them. It's really a constant process.