Canon Speedlite 430EX hot-shoe clip-on flash

Pros: powerful enough for most work, and good price

Cons: only a slave flash, need the 580 for master control

Summary: I usually shoot photos using ambient light without flash, this is only for occasional indoor photos of family and friends. For my occasional use, this flash is good enough. I almost always use it with the Gary Fong lightsphere II diffuser to get a softer look. The clear version of the diffuser works better. But if you use a lot of flash or plan on using multiple flash units, get the 580 ex speedlite instead.