Many years ago I played some Flash browser game, I forget what the actual game was about, maybe building a town or a tower or some such. When I finished the game, it posted my score to the online scoreboard. But I noticed that my browser showed an extra item in its browsing history, and checking that entry, I found that it had a URL with my score as a URL parameter. I copied the URL, changed the parameter to 9999999999999, pasted that back into my address bar, and got my name near the top of the scoreboard. (Not quite at the top, but the top few entries had evidently done the same thing with larger numbers.)
Many years ago I played some Flash browser game, I forget what the actual game was about, maybe building a town or a tower or some such. When I finished the game, it posted my score to the online scoreboard. But I noticed that my browser showed an extra item in its browsing history, and checking that entry, I found that it had a URL with my score as a URL parameter. I copied the URL, changed the parameter to 9999999999999, pasted that back into my address bar, and got my name near the top of the scoreboard. (Not quite at the top, but the top few entries had evidently done the same thing with larger numbers.)