Really clever concept on it, and while it was tricky in more than a few places, I feel the coin placement was perfect for guiding us through the levels. I liked and hated that it forced you to commit to your movements -- no tweaking up or down, since you're far more likely to ram your head/feet into a wall, then. My only issue is that in the web version, if you died a lot (I did), then eventually the SFX would get a bit buggy and static-y.