You may want to consider further defining what you want. You need to decide if you want the accumulation to be at every cell in the raster (not likely what you want), every cell on the stream, at regular intervals along the stream, specific points of your choosing, or at confluences.
If you want to do the latter, you could use the number of cells variable in the Stream Definition step to "granularize" the number of points/confluence you get along the streams. You could use the stream order function to eliminate minor streams if you don't want points on every little tributary.
If you come up with a way to do this from a point, then you can convert your stream raster to points and geoprocess this for every point on the stream.