Reachmahjong.com

Hmmm, but that's not a legit online Mahjong, right?

Well I was presenting it as a TV appearance, not a video-game one!

I know computer screens in films are often faked, especially when they show someone "hacking". Some efforts look better than others. In this case it's pretty detailed, with tile graphics, greyed-out buttons and a brief animation. It would be easier to use a real game than to spend hours making assets for a shot that lasts only a couple of seconds.
Then again, "Mahjong Online" would be a kinda lame name for the software! Feels like an art designer's exposition.

Elsewhere the show's attention to detail is lacking. This hand is described as Thirteen Orphans!

Oops! So they didn't want to bother reading the rules and showing a valid hand, but they sacrificed their precious time to make a mock Mahjong game...

Oh well, nobody but us, Mahjong freaks, will care anyway!:D

Only a mahjong obsessive with a quick finger on the pause button would've even seen it!

Here's another mention in Seinfeld.

In the 1994 game Virtua Fighter 2 the hobby of Kage the ninja is given as mahjong.
VF2 and mahjong are available as two of the many playable minigames in Yakuza 5.

As usual there's also an advert for MJ5 in the arcades and you can look at an issue of the Kindai Mahjong manga (with Akagi and Washizu on the cover) at the konbini.

You can visit a mahjong parlour in the classic Sega video-game Shenmue. (1999)
(Thanks to CaptainSyco's stream for the screenshot.)

A mahjong tile is an unlockable alternate costume in the game Super Mario Maker! (2015)
https://youtu.be/Iq8sRYh8yZw?t=8m44s (with mahjong speech sounds!)

http://www.mariowiki.com/Costume_Mario (#97)

You can collect mahjong tiles and scoring sticks in the video-game Shin Megami Tensei: Devil Summoner 2. (2008/9)

In the original Japanese version of the game this unlocks a mahjong minigame.

Osomatsu-kun was a manga from the 60's about sextuplet brothers.

Crunchyroll has one of the anime adaptations available and the first half of episode 21 sees the brothers playing mahjong.
Watch here with English captions: http://www.crunchyroll.com/mr-osomatsu/ ... tsu-692245 (free with ads)

The writers happily included plenty of mahjong terminology - and a brief appearance from a familiar face.

(Thanks to Scott for sharing this.)

Watched the mahjong part. Once. That was enough. Not exactly sure what the image was on the 1 bam. Pretty sure it wasn't a bird. Looked like a cat with glasses with a big green hat.
Must have missed that familiar face, maybe I didn't go far enough, or it just wasn't familiar to me.
Watching it though reminded me to check on that saki biyori anime again. Its been a while.

There are plenty of novelty sets with non-standard designs, in fact I see there was even an Osomatsu-kun set for playing Ponjan (simplified mahjong for kids).
In this case the cat is probably Nyarome (or "Nyaroko") who seems to be a recurring character in the manga artist's works.

Around 7'45" of the MJ story one of the brothers appears to be channelling Akagi briefly.

Is that Nobita?

I did actually wonder briefly if the cat was Doraemon.

There are several similar features but Nobita wears glasses.

I've just come across this:

https://www.youtube.com/watch?v=MAsxojdJUKw

Nice find! RIP Garry.
Here's a big mahjong sign in the video-game Sleeping Dogs: Definitive Edition.

Hong Kong looks great in high resolution on the PS4 but sadly the playable "mahjong" minigame is still the simple poker variant from the original PS3 game and when you see people playing proper mahjong outdoors several tiles (and players) are still missing! (see previous pics)