The Mythbusters cement truck explosion was probably nearly as big. They were made to stand a long long way from the explosion.
Nearly as big? When I saw it, it sure looked to me like the cement truck explosion took the cake in the size competition. Not that the exploding carshuttlebomb wasn't dead cool itself.
I was a little confused as to who you were quoting there for a second.
Looking at the mythbusters vid again, I think you're right. The Top Gear explosion was more flamey, and I grew up watching the A Team, so I'm partial to a nice flamey explosion. The mythbusters cement truck was completely obliterated so it was bigger. Remember watching it and thinking about certain events in Iraq and Oklahoma City.
I saw the newspaper crossbow episode of mythbusters last night. They got me thinking about what could be done with laminating paper with something more like superglue.