LEGOs and Lincoln Logs are for Luddites. Sifteo cubes are the new building blocks.
Each cube has a 128-pixel color LCD screen, wireless connectivity, a 32-bit ARM microprocessor, and an accelerometer that responds to tilting and stacking. You can arrange them to create everything from vocabulary puzzles to building challenges, all of which can be enjoyed by as many people as you can crowd around the coffee table.