Also into the harbour: The Thai International Airways flight in 1967 with 24 deaths and before that the US Marines Hercules in 1965 with 59 deaths.It may seem scary from the passenger's perspective, but actually that classic Kai Tak landing to runway 13 (the one from the west, coming in over Kowloon) was reasonably safe, statistically speaking. There were no crashes over Kowloon on approach to Kai Tak from 1951 to 1998, the year the airport was closed (and thankfully so, the no. of fatalities involved with a plane crash into the densely populated Kowloon city would be too horrific to imagine). The few crashes on approach before that ended up crashing into the hills around Lion Rock as opposed to hitting the city streets below.
The more recent landing crashes that happen at Kai Tak were planes overshooting the runway and sliding into the harbour. A CAAC trident, (as the airline was then known, before splitting into the major Chinese carriers we know today), a Lufthansa 747 in 1983 and several China Airlines aircraft (the Taiwan-based carrier, they had a rotten safety record since it's inception until relatively recently):
http://gwulo.com/node/6179
Contrary to what some in the media were saying, Kai Tak was closed not because it was deemed too dangerous, but because the air traffic volume had gone way pass the capacity limit of the airport. And with the airport unable to expand (since Kai Tak was surrounded by urban areas), Chep Lap Kok was build.