fpcup is a tool that gets the current (or a stable) version of FreePascal Compiler (FPC) and Lazarus IDE from their subversion repositories and compiles/installs them.
It adds CHM documentation and configure the Lazarus help for you.
It also creates a shortcut on your desktop/home directory that points to the new Lazarus installation.
Meant to be used side by side with other FPC/Lazarus installations. It creates a separate primary config path directory for the new Lazarus installation, so it doesn't interfere with existing Lazarus installs.