I have used Micro-4/3 system and kit lenses that came with my E-PL5 for a little while. The Olympus 14-42mm and 40-150mm zoom lenses are good lenses for outdoor use in good lighting but indoor photos have not turn out consistent with these lenses due to their small apertures. I have done research on many lens models available to this system and came to the conclusion that a bright compact prime lens would nicely complement the kit lenses. However, from all the research, the only thing I came up with is that there exists a wide selections of M4/3 lenses of various focal lengths and aperture ranges. As a newbie, I didn't know how to choose. Some members suggested that the best way to determine what lenses to buy is go through one's library of photos to see which focal lengths one tends to shoot in the past. Great idea but how would I do that systematically? I have over 20,000 photos accumulated over 13 years. To effectively tally what focal lengths and apertures I have been using most in order to choose the right lenses, I need software to tally up all these usage statistics. I couldn't find any such software that does this effectively so I rolled my own application. It has helped me to find my trinity prime set of 14mm/25mm/45mm the scientific way. I realize that the program I have written may help other users to select the right lenses for their kits. If you wish to give it a try, you can download it from my website at http://www3.telus.net/lens-gas. This software is a labor or love from this hobby. It is and will always be free and you can share it with anyone you wish. Give me feedback as you please.