[widebody911]

From what I've read, at leat for BTC, it's a waste of time unless you have a lot of resources to commit to it. People are hiding mining software in websites now, so when an unsuspecting rube visits the site, his machine starts mining in the background. I wouldn't be surprised if some of those "casual games" eg Candy Crush aren't doing this as well; I know the fan on my wife's laptop goes nuts while she's playing.