Luigi's Mansion is on the Nintendo Gamecube, not the DS. I should know. I own every Nintendo console and handheld except for the Gameboy Light (released only in Japan but available on online auctions) and the Virtual Boy (a 3D headset system portable like the gameboy. Known to cause headaches).
There is a rumored second game coming to the Wii, but it is still a rumor.
The game, though lacking in difficulty, consists of Luigi Mario, brother of the famous plumber Mario Mario, who has unexpectedly won a contest he didn't enter for an extravagant mansion somewhere in the woods. Mario goes in search for the mansion but never returns. Luigi heads to the mansion only to be scared half to death by the boos that inhabit it. Professor E. Gadd (Elvin Gadd), after a big problem with his previous laboratory (Mario & Luigi: Partners in Time) is hiding in a shed outside the mansion to study the boos. He gives Luigi a vacuum that can drag up ghosts. A bit scared but willing to save his brother, Luigi accepts and heads into the mansion. You meet up with the Prof. Later (You may remember FLUDD from Super Mario Sunshine "made by Gadd Science Inc.")
The game is based mainly around exploring the mansion and capturing ghosts with the Poltergust 2000 (your vacuum) and unlocking new parts of the mansion to get to Mario. If you're into a good game without any freaky parts, Luigi's Mansion is for you.
The game is intended for Mario fans and is the first game that Luigi is the main character. Some people consider it his big break, even though the game is still based around Mario.
The Nintendo DS handheld system doesn't have a Luigi's Mansion title, but the future is still unknown for our green plumber. If you need a good Mario experience on the DS, pick up Mario 64 DS or New Super Mario Bros. You won't be disappointed.
I give it a 7/10.
this has been tried with custard as well. if you fill a pool with custard, and run across it, you won't sink an inch, but stay still, and it'll make you sink. If you try to get out of it, it'll pull you back in. custard, when being affected by motion, will turn into a solid, but when standing still, it will act like a liquid. thus if you stand in custard, you will sink, but you can run across it too, because your running is affecting it with motion.