I bought a new camera of E-Bay a Canon PowerShot230 HS it's a few years old but it has loads of features and in someways better than my old Kodak Z1012. It only cost me £69 which I think was a bargain. It didn't have a memory card but I used the one I got with the cheapo 60fps kodak I bought a while back just to try some slightly slower motion filming.
The big advantage is it will shoot at 120 and 240 frames per second. At 240 the resolution isn't so good but 120 fps gives a good idea of arrow flight. Note:- The video is further slowed in Windows Movie maker which allows 0.5, 0.25 and 0.125 speeds.
I couldn't resist playing about and mounting it onto an old hard hat, it took a lot of messing about to get it in the right place at the right angle so you can see an arrow go. You can see a hole above the temple of the hard hat where I first tried to mount it. I used the camera mount from a broken old camera tripod, I knew it would come in handy one day.
It's mounted to allow for the tilt of my head in my normal shooting style. I s'pose I could use my old camera on a tripod to get some video of me shooting with the hat cam on!