I posted this image in my Block Play blog today, but I'm not sure the Archie & Webby fans check there for cat pictures.
What? The dinosaur-robot doesn't look much like blocks? Well, I use "building blocks" with some figurative flexibility, and include many non-rectangular things where reusable elements are used to construct. Legos, Lincoln Logs, Erector sets, Parquetry Blocks, and more - and of course, nice, rectangular Building Blocks. Stack play, techno play, pattern play, whatever.
It's my blog, and I make the rules. :)