FreeLM
Tool for creating, pruning and interpolating N-gram models
...It's similar in spirit but modified, interpolated Kneser-Ney, but uses the principle that the amount you discount should always be the amount that gets given to the backoff state (which makes the traditional count-of-counts stuff and the associated formulas for obtaining smoothing constants unusuable).
This gives slightly better results than KN for standard LM building, but has larger advantages for interpolation and pruning. See <a href=freelm.sf.net> here </a> for documentation.