Okay, the finished flaregun. I used a cardboard tube and some cardboard boxes, and to bulk out the shape, I used tissue paper (or toilet paper) and dipped it in PVA glue (the white liquid glue used in primary schools) to form the shape.
Last night, I finished a Detonator. Because, when it was unpainted, it looked like the Flaregun, and because I ran out of dark blue paint, I painted it light blue.
I also finished my syringe gun but I completely botched up the bit where the syringed are supposed to go. I also simplified a lot of it as it just doesn't work well in cardboard. On the plus side, because it IS made out of cardboard, it's really light, so it'd be quite good for a convention.