Last but not least come puzzle games. These come in many forms, and the two I've picked out could not be any more different from each other.
The first, We Create Stuff's Interlocked, is an intricate 3D Flash-based game in which you must rotate geometrical shapes composed of interlocked pieces of matter, and slide and shift their parts until you eventually manage to take remove each piece from the larger shape. If you enjoyed playing with Lego blocks when you were little, you'll love Interlocked.
The second puzzle game--this one produced by Gopherwood Studios--is Entanglement. Based on HTML 5, Entanglement is played on a hexagonal board. Your goal is to place new tiles on the board in such a way that you string together the longest continuous path possible. Very addictive, surprisingly difficult, and yet soothing, too.
So go ahead, click through and play for a few minutes. You'll be glad you did.
For a complete list of the games mentioned in this story, with brief descriptions of each, see our browser-based games collection page.