There are a handful of X-Com games.
The second title (Terror from the Deep) is essentially the same game with an aquatic theme (it's also available for the PS). It suffered from some rather bad bugs regarding the research tree, which could potentially make it impossible to complete the game, but did offer a handful of improvements as well.
The third title (Apocalypse) qualified as a proper "new" game, and it's very good (though opinion is divided over whether it beats the original). The GeoScape is replaced with a CityScape populated with other organisations, who battle with one another and form alliances etc. For example, the police and goverment are on your side, but the alien-loving Cult of Sirius just wish you'd leave their otherworldly friends alone.
So you can, if you wish, level the entire city and send in your ground forces to steal equipment. That plus the option to play in either real time or turn based mode, and the ability to demolish entire buildings by taking out the supports, makes it pretty cool.
Then there was Interceptor (UFO meets Wing Commander) and Enforcer (you're a robot built by an Ex-X-Com scientist, running around in 3D person blowing up all aliens in your path). Neither game was really that good, and due to a whole bunch of companies being shut down the series basically died as the rights got passed around.
However, the current buzz around the web is that the current owners (Take2) might be (read: probably is) working on a new title, and that the developer they've assigned to the task is Irrational (the guys who worked on System/BioShock). They refuse to admit anything however.
If you're looking for a modern equivalent, take a peek at ALTAR's UFO series (inspired by X-Com):
Aftermath/
Aftershock/
Afterlight. They turned out to be quite popular.
Kart 64 seemed to use a "Doom" style 3D for the racers - Lots of 2D sprites, displayed according to the angle the racer was on. I suppose a
couple of
videos would show the difference better then I can explain it.
So yeah, that turbo move does look similar. Guess I just didn't understand the 64 versions controls that well.