Cracked itself isn't written to intellectually stimulate, but you're right that it can be. Their lists are frequently excellent starting points for Wikipedia/research binges, as they cover a lot of interesting topics. I'm often turned off by their style, but there's no denying that they've covered a lot of interesting things in their articles, albeit usually with a brief summary and a joke.

Putting a little more thought into this, I think good comedy is always intelectually stimulant...

the unusual parallels bend your perception of things, bullshits we all passively accept are mocked full up... its the type of thing that makes you 'think out of the box', see the leaps in stuff, ignore bullshit, etc

so, some stand-up and cracked are on my list on this