I'm a fledgling game designer and for practice, I'm currently working on a from-scratch side scroller engine to host a game that will be entitled "Toad's Adventure: The Return of Wart."
I'm not going to reveal too many details about the story line, but you can probably figure it stars Toad. I think he's the most neglected character of them all, and he happens to be my favorite as well ;) Mario will make appearances in the game and will be relevant to the story line -- you'll have to help him out of more than one jam over the course of the game ^_^
Its a C program that will run in DOS and uses the (in)famous Allegro game programming library. I'd estimate the engine is about 10% finished, so I have a lot of work to do. Sound effects, music, and graphics progress is better though. I'd estimate 80% on the sound and maybe 20% on graphics.
This is a private project since its obviously a blatent copyright violation. I'm just making it for my own personal education and entertainment. However if people are interested in playing it, I may provide a covert download location when its ready ;) I know my friends are excited about it. I hope that others will like it when its done.
James