We got a Wii U for Christmas, lovely piece of kit (if you like Nintendo, obviously) and one of the nice touches is a big gamepad with its own high resolution screen that you can actually play most of the games on without having to hog the TV to yourself.
This apparently works using some proprietary technology over a standard 802.11an 5.8GHz WiFi link back to the main console (lots more detail/guessing is here in this excellent Digital Foundry article: http://www.eurogamer.net/articles/digitalfoundry-secrets-of-the-wii-u-gamepad).
This was working really well up until the other afternoon when I was working on my laptop (a Mid 2009 MacBook Pro) and Tom (my son) was trying to play Mario Kart. He kept complaining that the screen on the gamepad kept going "all zig-zaggy", but whenever I closed the lid on my laptop and went to look it played perfectly. I guessed it may be something to do with interference from my laptop, as it also uses 802.11an to connect to our Airport Extreme access point. I confirmed that my iPhone 5S was also causing the same interference and, in some instances, causing the gamepad to completely disconnect from the console!
There's no way to change any of the settings for the gamepad on the Wii U. I've no idea if it even scans the local spectrum to choose what channel to use or just plumps for the same one all the time as it's not visible with a normal WiFi network scanner (I'm sure a proper radio spectrum radio analyser would be able to see it, though, and I may borrow one from work next week). My only option was to try and change the settings on the access point to alleviate the problem.
First off, however, I moved the access point. It was initially right next to the Wii U and this could easily have been affecting the Wii U's operation. I've managed to put about 18" between them now, but space is limited around my TV cabinet. Next, I delved into the radio settings on the Airport Extreme. At some point in the past I'd had some issues with neighbours running aggressive wireless networks that caused drop outs for me and I'd manually pegged all my radio settings. This, of course, gives the AP no opportunity to reassess the state of the radio spectrum and change its channels or the protocols used. I changed the 2.4GHz and 5GHz channels back to "automatic" and also changed the radio mode back from "802.11a/n - 802.11b/g" to "802.11a/n - 802.11b/g/n (Automatic)". Top tip: if you have an Airport Extreme, doing alt-click on the Radio Mode button gives you a lot more options for how you can run the radios in your AP. You shouldn't need to, but it's there if necessary.
(I must admit to not fully understanding these settings and need to have a chat with the guys at work who look after our wireless to get up to speed. I believe 802.11n denotes use of MIMO for higher speeds, and 802.11a means it uses 5.8GHz, allowing up to 300Mb/s. 802.11b/g are the older 2.4GHz modes that allowed up to 54Mb/s speeds but I'm not sure what 802.11b/g/n entails)
The only 802.11b/g devices I have in the house now are the Wii U (for it's Internet connection; it has no wired interface), our 3DS handhelds and a TP-Link wireless extender for the laser printer. Everything else (TV, PS3, WDTV, amplifier and PVR) is connected to the gigabit wired network.
Anyways, the 2.4GHz radio has now moved itself to channel 1 and the 5.8GHz is happily up on channel 100 with no interference from the neighbours. I've tried hammering the wireless (doing a Time Machine backup over the 5.8GHz is always good for that) and playing Mario Kart with no ill effects, so it looks like it's sorted now.
I'm sure this will all break horribly again at some point in the future, but that's just the joy of (home) IT...