Put the warning there since I can embed a whole freaking real-time model viewer onto a browser.
Basically, Sketch fab allows you to view models in real-time, and share them. Which is pretty dang cool, IMO. It's also free, so why not?
I'm more of a SFM user, myself. And the fact I never upload stuff I make here (except one-off flash games), seems to be a bit boring. I tend to make random weapon models, and some source models from time-to time.
I will only post an example, since 1 model is enough to lag most PCs to death. Due to how KYM sorts their forums, I recommend clicking full-screen to see some models.