Glass Shatter
Press any button on the little site. A clear pane of glass sits in front of it, invisible head-on, and it breaks from the exact point you pressed, even off-centre on a button.
The cracks are a spider's web, like a real impact: splinters at the hit, slabs at the edges. As the shards turn they catch a studio baked into a reflection map, and the new page bends through them, text and all, splitting into colour at the edges.
Every shard's flight is worked out once, on the click, and played back in the vertex shader. Between breaks the canvas is empty and the real page shows through untouched.