If you're looking for something small, either the SB-18 or SB-30 will fit the bill. SB-23 also works. If you want something with bounce capabilities that's still somewhat small, check the SB-15 out. Bounces upward when the flash is right side up, bounces to the right if it's vertical, or downward for macro work if it's upside down. The SB-27 is the more powerful, more modern version of the same. With that flash unit, the bounce features are the opposite and are handled by a bounce card. If you're looking for a more conventional flash that does TTL, there's the SB-16B, the SB-20, 22, 22s, 24, 25, 26, 28, 28DX, 50DX, 80DX, 600, and 800. All those are shoe-mount and have a bounce head, but aren't shaped like a horizontal pack that sits on top of the camera. You can also get by with the SB-11 and SB-14, if you use the SC-23 cable. Macro is handled by the SB-21B, the SB-29, and the SB-29s.
-J