After years of playing something interesting/different must have happened to you in game? One example I have is a VERY long time ago and wouldn't work now and nor would I even try this now, I discovered a glitch on the Runescape forums allowing you to post on it as another player without knowing their username or password. It was pretty easy, I noticed when you logged into the website the URL would have a long number in it, I figured this was somehow connected to your account, I asked a friend to test this out with me and I got him to log into the RS forums and send me his unique number in the URL, I then logged into on my account, switched the number and I was suddenly on his forum account and I made a post to test it. As soon as they logout on their computer it would log me out too. I never abused or reported this....and no you could not change someone's password or anything doing this.
