Some people desire methods with a smaller standard deviation (more tightly centred about the mean) than the standard 4 FUDGE dice. Others want the opposite or some sort of hybrid. Many alternatives have been discussed.
The following applet allows the interactive visual exploration and comparison of many of the schemes proposed. Up to four different distributions (dice methods) can be displayed simultaneously in a variety of colours. Simply use the pull-down choice boxes on the right of the graph to select the method (and colours) of interest.
If the above applet is not working then it is likely that your Browser does not support Java 1.1 but the older 1.0. I have another version of this page who's applet supports the older language features (Event model). Therefore try it if nothing is being displayed. However, be warned that that page may be out-dated.
dF are FUDGE dice: a six-sided dice which is marked with two +1s, two 0s and two -1s. For instance 3dF means roll 3 Fudge dice and add their totals together (yielding a result between -3 and +3 inclusive).
To the end of the description of non-FUDGE dice is added the number of sides that are positive. The same number are negative and the rest of the sides are treated as zero. For instance d6.1 is a six-sided dice with one side marked +1, one side marked -1, and the other four marked zero (i.e., the sides are {-1,0,0,0,0,+1}).
Finally, its also possible to use other values than +1 and -1 only. In these cases the notation records the number number of each value. For instance d12.3.1 means a twelve sided dice with three sides that are marked positive. One of those is a +2 and the other two (3-1) are +1s {-2,-1,-1,0,0,0,0,0,0,+1,+1,+2}.
Spike's Roleplaying Page