Here's one example: Are there any English servers where I can play Mahjong online?
Um, well, I think something like VASL would be on-topic for anything but a tech question (
belongs-on-superuser) but anything you couldn't resolve manually is firmly off-topic.
Since I created both the question and the Mahjong proposal at Area 51, I'd like to add a few remarks.
The Gaming.SE site it about computer games, mahjong behaves more similar to card games than to the games there. Also, I am going to ask many other questions about Mahjong itself (having nothing to do with playing online).
The proposal was closed because it is "a subset of Board and Card games". So either the question should be allowed on this site, or the proposal should be reopened. I personally believe that the proposal was closed rightfully, because this site can provide a home for Mahjong.
It's a tricky one, as the expertise here is naturally online-savvy and slanted towards board games, but I'd say no, not when it is purely about the online version. It's better suited to gaming.stackexchange.com.
The clue is in the title of the site - 'Board and Card Games' ;)
I toyed with reposting my 'Is there an iPhone/smartphone version of Diplomacy?' question from gaming.stackexchange.com, but if we allowed those types of question we'd open the flood gates to all kinds of 'I like X, where is it online' questions and a lot of overlap with gaming.stackexchange.com.
To put it another way, of the two sites, where would you ask 'I like Half Life 2, what board games would i also like?' - probably not gaming.stackexchange.com.