My sister-in-law is begging me to bring our Wii with us when we travel to Chicago for the holidays. However, there's no way I plan to pack it in my luggage, as I could see it being treated as "a suspicious electronic device/hey my niece would love one of these" by the baggage checkers.
So that leaves bringing it as carry-on.
But, unlike a laptop, I can't just "turn it on to show it works" like you can with a laptop, PDA, or MP3 player. I will also be traveling with my wife and kids, so having a big hold-up in the security line and having some jerk security worker decide to give me hassle for bringing it is not an option. (Especially if they decide to really be jerks and won't let me take it.)
So how am I planning ahead? By bringing a USB video-input device. You know, like those USB TV-tuner devices that have video inputs on them. This way if anyone in security really has a beef with me bringing a Wii through the line and wants me to "prove" that it's really not a bomb, then I can just fire up my laptop, plug the Wii video cables into the laptop and show them right there.
Granted, this is a worse-case scenario, but the USB video-input device is really small, so it's no problem to bring it with me, and I'd rather be prepared than up a creek when traveling during the holidays.