In experimental psychology with normal subjects it is almost universal that we repeat many (usually orthogonal) treatments on the same subjects, so we end up with a factorial within-subjects design. I know of nobody in my general area (vision research) that does anything else. Yet for some reason those who write statistics programs appear uninterested in this type of design -- being tuned more to the social psychology type of group differences. This is a pity because there is almost no software that does this type of analysis (except the high priced ones like SPSS -- and even they do not do it well and are unable to plot the results with the correct error bars). If StatistiXL had that facilty I predict it would be the favored software in experimental laboratories. Given that it does the between-groups factorial analysis it should not be much of a trick to add this feature which would be much appreciated.