All developers and coders would agree that we read and browse code more than actually write it. Hence it is important that we all have proper tools to browse the code. If you use GNU/Linux, cscope is a good choice. If you use Windows, SourceInsight and Eclipse is a good choice. But what about the open source code provided to you as libraries. If you ever in such need, head to the below link for Open source Cross Referencer. This will save you the time and effort of syncing code and browsing on your PC when you can do it instantly online.