Here are some links to several attempts at running various kinds of behavioral experiments in a browser:
Using PIXI.js and it's 'tink' extension, the mouse cursor it replaced with an image and it's position is rotated by 30 degrees around the centre of the screen. There's also some code to try to make the experiment as large as possible for optimal resolution of mouse movements, but that doesn't work so well yet:
Link: Rotated Rocket
Built from scratch in JavaScript, this task requires people to first press the space bar along with the rhythm played in the browser, and then keep playing that rhythm while there is no more sound. This tried to use e-mail to send data back to the researcher, which kind of works if you're next to the participant, but that is not what we want ultimately.
Link: Tap Task
Here is a search task. It starts with an example informed consent page, although the text there is so long that it will likely not achieve it's goal: inform participants of their rights. We need a much shorter form, for it to be effective.
The search task involves finding the item where the little crossed out section of the line is at the top, not the bottom. Once found, the participant should indicate if the line tilts the left ( \ ) or if it tilts to the right ( / ), by pressing the left or right arrow buttons on the keyboard. On most (but not all) searches there will be a cue to guide the participant, by indicating the color(s) of the disk that the target can be in, or by indicating what color(s) disk the target will NOT be in. There is no attempt here to store any data yet.
Link: Cued Search