I saw this video yesterday for a game that looks very similar to Super Mario Bros 1-1. Whoever is responsible for creating this game has an evil streak that would make Hannibal Lecter's culinary streak seem positively tame in comparison.
The real genius in the design, is it takes everything that you know about a level that is familiar as the back of you hand and turns it on its head. I found this here
and although it says you can download and play it yourself i wasn't able to decipher the Japanese writing after the link. In some ways i'm sure this is a good thing i don't think i would be able to handle the fustration without smashing my computer to pieces. Watching a video of someone else try does provide some amusement though!