Welcome!
Five Speed Software is best known as the creator of Dash Board, the ultra-mega-smashingly-cool interface enhancement for the Newton. Yes, you can still buy it! All of Five Speed's old Newton apps are free now, and all the purchase links now point to the free registration code generator. (There is also an open-source option, for those with some spare time.)

Five Speed's complete Newton product line is listed below; click on a product for all the details.