The Polyomino Tiler lets you explore grid-tiling with different
sets of polyominoes (such as the tetris pieces,
a.k.a. tetrominoes). Using whatever set of polyominoes you
specify, and whatever grid-shape you create, it uses a
moderately-optimized search algorithm to try to find a way to tile
the grid with the specified polyominoes.
It has all of the dominoes, triominoes, tetrominoes, pentominoes,
hexominoes, and heptominoes. The grid can be wrapped around
either or both axes (which can be used to create seamless
repeating tile patterns).
If you create a grid or a tiling that you want to save, there are
a couple options. You can simply download an image (with the
"Download Image" box), or save the grid/tiling permanently on the
server (with the "Persistence" box). In the latter case, links are
provided both to restore the grid/tiling/configuration in this
explorer, and also to permanent image files (which can be used,
e.g., for sharing and embedding).