Nikon SB-800 Flash
I ordered several from Amazon but I would also trust the guys at Adorama.
This flash is the top of the line in Nikon's current series of flash units.
The SB-400 is complete trash compared to this professional-grade flash. While the SB-600 is a close second to this SB-800, the SB-800 offers many features that only professionals need or would likely use.
Power source: Four or five internal AA batteries. This unit can also be connected to an external power source providing nearly instant recycle times.
Bounce Flash: Yes, even includes a built-in bounce card.
AF-Assist Lights: Red and a lot less annoying than the on-camera white assist light.
Works on a film camera: Yes.
Controls: Yes, this flash has buttons and an illuminated display.
Wireless Control: Nikon CLS (Creative Lighting System) that uses IR and a port for wired or other wireless trigger. This flash can act as the slave or the master in the CLS system.
Recycle Time: Varies from a few seconds with 4 batteries to nearly instant with an add-on external battery pack.
Stroboscopic: Yes. This is the feature that lets you make those physics text book images of the ball being dropped and you see it as gravity accelerates it. Not something I use a lot, but not a terrible tool to keep in your arsenal.
Front and Rear views of the Nikon SB-800 Flash
This flash has performed flawlessly at every event I have taken it to. It hasn't quit on me at all and it has been a pleasure to work with it in the field.
If you are professional photographer who requires a flash unit for income, then this is likely the flash you will want.
If you are merely an advanced amateur or a part-time professional, you will likely be just as well served by the SB-600 flash which is about 95% the same flash but for 60% the cost as measured when I wrote this review in May of 2008. The SB-800 is selling for over $320 while the SB-600 is $190.