Columns is described as 'Tetris style puzzle game where you align colored blocks to clear rows'. There are more than 25 alternatives to Columns, not only websites but also apps for a variety of platforms, including Android, Windows, Linux, iPhone and Mac. The best alternative is Puyo Puyo Champions. It's not free, so if you're looking for a free alternative, you could try NullpoMino or Hextris. Other great sites and apps similar to Columns are Quadrapassel (Free, Open Source), Blockinger (Free, Open Source), Tetris Blitz (Freemium) and Tetris Online Poland (Free).
In Quadrapassel, the GNOME version of Tetris, your goal is to create as many complete horizontal lines as possible. The lines are made from seven different shapes. The shapes fall randomly from the top center of the screen.
Tetris Online Poland (TOP) is an online tetris game where you can play tetris with your friends and tetris experts from all over the world. You can also challenge your own records or train yourself against a bot.
1010! Klooni is a free, libre and open source klooni of the original minimalistic puzzle game by Gram Games. Fill Up the Board: Drag the pieces on the board and try to clear as many strips as you can! Beware though, it is not that easy o:)
Play the popular tetris arcade game on your Mac. This classic puzzle game is easy and fun to play and suitable for kids of all ages. Use the arrow keys on your keyboard to move the and rotate the blocks.