Play Super Mario Brothers online.

[Dinner]

http://www.fullscreenmario.com

It not only has the full game but it also allows you to jump to any level you want and even includes an editor to make your own levels.

[Mary Lenihan]

Super Mario bros is one of my favorite games since childhood and I often play this game online. Thanks a lot for sharing such a wonderful link .I would love to play by using the level editor option in the super Mario brothers.

[giblets]

Taken down. I guess I'll just have to use an emulator.

[DaShi]

I guess I'll have to buy a WiiU now.

[Hikapo]

Its taken down :X