Lazarus Ide is for FreePascal. You create forms, like in Delphi or Visual C++, or Qt, or GTK.
Lazarus is cross platform, but works better on Linux. It creates smaller binaries on Linux than it does Win32 ;)

Some common applications built with FreePascal:
*SeksiCommander
*Lazarus itself ?
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Lazarus is also a good tool for CGI development,  not just GUI's for Linux and win32. 
If you find you need to build a very small application, lazarus LCL may not handle this nicely yet, until the LCL is linked more externally. You can still use lazarus ide to develop non LCL applications. It's much more comfortable than FP-IDE (free pascal IDE).

Lazarus includes 
*code completion on the fly. Press CTRL-SPACE and you receive instant information for the keyword you are completing. 
*multiple windows and tabs
*Object Inspector
*TreeView
*Target CPU.
*Compile everywhere: Linux, Win32, etc. Even compile a win32 on a linux machine.
*Smart-Linking  
*Dynamic library creation is simple. For both ELF and DLL, just change "program" to "library".