Lino is a site that allows you to create and share sticky notes. A (free) registration is required to create a board, but once a board is made sticky notes can be added to it by users without an account, making it a great tool to use with a class. Sticky notes can be customized by changing the color and font size and by adding icons. You can also upload images to the board. Images and sticky notes can be rotated to create a more interesting-looking board.