We bought Wedgits last year for #2 to play with. The starter set was such a hit that we bought several other sets for Christmas, including the nifty car set, of which I have no pictures. Wedgits are square blocks that lock together to make cool creations. These two were built straight out of #2's imagination. We did buy a set of design cards that shows different ways to use the blocks - and that was actually a good purchase because the creators of Wedgits are smarter than DH and I and came up with more ways to use them than we could. Wedgits have brought us hours and hours of entertainment.
You can buy them from many, many places - we ordered from Rainbow Resource. I'll let you search and hunt for your own. Find more good toy ideas at Rocks in my Dryer.