You are a red square. You leave a trail of yellow squares behind you. Your mission: avoid the white squares and the blue wall. Advancing one row earns you one point. Once you smack into the wall or a block, the game is over. You can go diagonally left and down or diagonally right and down
This is JetLag in its purest form, and (for a flash game) rather similar to the original 6809E edition.
After playing it a little bit, you may consider this version too easy. This is not about how easy the game is to play for five minutes, nor ten minutes. This is a hardcore endurance game. Can you last 45 minutes without making a mistake? How about an hour? The game scores at a rate of 12 points per second, approximately. 720 points per minute. 43,200 per hour. I challenge you to go for 100,000.