You can play Oregon Trail to lose. The game is constantly trying to kill you and the members of your party, and its developers intended for you to try to avoid a cruel death by dysentery, snakebite, or cholera. But when I was in middle school, where Oregon Trail was installed on our colorful iMacs as educational software, my friends and I usually had more fun naming our party members after one another and doing our damnedest to kill everybody off. Set your pace to grueling, set your rations to meager, ford the river even when it’s thirty feet deep…this was how we played. The faster everyone died, the better. Bonus if you keep the character named after yourself alive the longest.
I think Oregon Trail is unique, or nearly so, among computer games in that it is possible to play it, and have fun playing it, in a fashion that the developers did not intend, without any hacking, mods, or cheating. Oregon Trail is really two games: the game that was created on purpose, where the goal is to get to Oregon, and the emergent kill-your-friends game. The existence of the latter game depends on the rules and mechanics of the former, but it also depends on those rules and mechanics being free-form enough to allow the alternate style of play. I don’t think there are any other games like this, where it is possible to play through the game while pursuing your own goal, without the “actual” goals of the game getting in your way whatsoever.