Torrent 3GP Cutter is a video edition tool for Windows. It allows you to cut your video files and create shorter clips from them. The application lists support for quite a few input video formats, such as DivX, XviD, MP4, FLV, MPEG, DAT, WMV, ASF, and MOV among others, but it can only open 3GP files. Videos cut using it will be saved in the 3GP format, as well.
Using the application is very easy. The first thing you have to do is load a file. After the file is loaded, the built-in video player will start playing the video. You have to select the part of the video that you want to keep by using the "Start time" and "End time" buttons, which will create a selection that will be added to the right part of the screen. You can set as many selections as you want. When you are done, and after clicking on "Start" the application will start processing your files. It will create one file for each time range.
In my testing, I used a sample 3GP file that I cut into a 1-minute clip. The process took less than 5 seconds, since there isn't any re-encoding needed for video cutting when the input and output files are encoded using the same format.