In Elona+ [official site], your backpack can crush you to death. In most games, the worst that is likely to happen if you're overburdened is a reduction in your speed but in this excessively strange Japanese roguelike, the weight will drain your health or cause you to trip, fall and break your face open as you try to navigate some stairs. It's a game in which you can make money by busking with a grand piano but if you're not particularly talented, don't be surprised if your audience stones you to death.
Yes, you should be playing Elona+ and what better time than now? Version 1.49 and the relevant English translation have just been released.
If you've never heard of Elona, you're in for a treat. It's a free game that deserves a place in the great pantheon of traditional roguelikes - stranger than most of the genre and sometimes so hectic that I can't fully parse all of the information it's throwing at me, it's an unusual and brilliant creation. Ancient Domains of Mystery (ADOM) is probably its closest relation, as they share the existence of a fixed overworld and main quest locations (as well as a puppy dungeon), but Elona is very much its own game.
You can download the latest version of the 'plus' modification here and the English translation - which isn't yet complete but will tide you through tens of hours - is here. I'd strongly recommend this beginner's guide and a few sessions with the vanilla game before moving on to Elona+ though, whether you're new to traditional roguelikes or not. Elona's rules are often obscure when first encountered, and it's entirely possible to lose a character without knowing quite what you did wrong. The vanilla game is considered complete, as is the English translation, but when you've become accustomed to it, graduating to the 'plus' version is recommended.
And remember - kill every bard. It's the right thing to do.