I know I have waxed on about these blocks before. And I know they are terribly expensive ($128 for a set of five, we bought two sets). But these are, bar none, the best toy we got for our baby.
Update to make the “buy these blocks at Constructive Playthings for $129” link more obvious.
These are huge, vinyl covered foam blocks. They are big, brightly colored, and light, so you can stack them high and knock them down without fear of damaging your baby. They come wrapped in black plastic, like a set of tires from Costco (or is that just a myth?), and ours arrived a little dusty. Our boy has always loved building things, and we’re not sure which came first, the blocks or the desire. But he’s almost five now, and still using them as much as he did when he was younger.
Here are just a few pictures of what we have done with them: