I built one of these flash triggers from plans in popular electronics in the early 90's. It was a lot of fun to play with, but used analog electronics and was a lot less flexible than what you can do with an Arduino.
I also used a flashflight because there were no cheap laser pointers, so my setup had to be pretty delicate because not a lot of light was hitting the sensor.
It was also kind of torture to have to shoot a bunch of pictures on film with no feedback on how it's coming out then develop the whole roll and see the same mistake repeated 20 times. It took weeks to get the technique right. With it digital camera today, it must be fantastic to play with this kind of photography.