Mario Kart DS
Nintendo DS Cameos

R.O.B.

One of the unlockable characters is R.O.B., the Robotic Operating Buddy NES accessory. In the Japanese version, ROB is "Famicom Robot" and appears in his original Japanese colours.

The ROB-BLS kart is based on R.O.B.'s Stack-Up set, with trays surrounding him. The ROB-LGS kart appears to stand for "R.O.B. Legs".

Submitted by Fryguy64

Cameo Karts

Several of the karts are references to other games:

Clown Car Copter

Bowser's Clown Car Copter is based on the Koopa Clown Car that he used in Super Mario World and Paper Mario.

Rambi Rider

Donkey Kong's Rambi Rider car is based on Rambi, Donkey Kong's animal buddy from Donkey Kong Country.

Submitted by Aquatics64

Nintendo DS Battle Course

One of the Battle courses takes place on a giant Nintendo DS.

Submitted by GameHiker

Super Mario Bros. 3 Icons

When you start the game, the icon that appears next to the 1-player mode is Mario's head from Super Mario Bros. 3. When the multiplayer game is loading, Mario and Luigi's 8-bit heads both appear, overlapping each other.

Submitted by YoungLink

Wario Stadium

In Wario Stadium, 8-bit sprites of a Super Mushroom and Star Man from Super Mario Bros., as well as the NES font, all appear on displays around the course.

Submitted by Wildcat

Shroom Ridge

On the Shroom Ridge track, the trucks feature sprites of Cheep Cheep from Super Mario Bros. 3 and Berries from Super Mario World on the side.