Now we can do all our work with open source application. Sometimes i have seen that people don't find or don't know which open source applications are available to do certain job. Here is a list of 50 top open source application by devid uhlman which we can use for beginner to enterprise level.This is a pdf file. I am giving here linkwhere you can download. This pdf also contains the regarding application site name where you can get the software.Have a look ,Have a fun!