Best price I can find online.
The second 'designed for the D40' accessory today is the SB-400 Speedlight, a compact yet powerful external flash with a tilting front (horizontal, 60, 75 and 90 degrees). This unit has a guide number of 21 (m at ISO 100 at 18mm) and has a shooting distance of 60 cm to 20 m (2 to 66 ft).
- Compact, lightweight Speedlight unit
- Simple, intuitive operation; Put it on, turn it on and shoot!
- 18mm angle of coverage with Nikon DX format digital SLR cameras
- Utilizes Nikon's i-TTL intelligent flash
- Operates on two AA-size (1.5V) batteries
- Fast 2.5 second recycling time
- Bounce capabilities in 4 steps up to 90 degrees
- Approximate guide number of 98.4 feet at ISO 200 (at 18mm zoom head setting), Flash shooting distance range from 2 and up to 66 feet
- Compatible with Nikon D50, Nikon D80 and Nikon D200