I decided to start building all the levels from Super Mario Bros in Minecraft. I've only just started world 1-2. XD I'm doing everything solo, in creative mode. But I'd rather if people went through it in survival mode or adventure so that pitfalls work properly.

UPDATE:
Finally finished world one! :D I'll keep updating it as I do more.

Additional Notes

It looks best with a texture pack that makes glass blocks completely clear. Personally, I use Torhan's Clear Glass 1.5 No Border texture pack.

http://www.minecraftforum.net/topic/1135981-151-torhans-clear-glass-default-texture-pack/