Super Mario Bros Flash is a Super Mario Flash hack developed by TheRussian.
Themes
The hack is themed about Super Mario Bros for the NES, but also includes some sprites from other NES games, like the Dry Bones and Boo. This hack was used quite a lot when it came out.
World Map
Since there was no World Map in the original Super Mario Bros, TheRussian decided to give the world map a Super Mario Bros 3 look.
External Links
Super Mario Bros Flash on TheRussian's website.