NSIS Alternatives, Similar

NSIS (Nullsoft Scriptable Install System) is a professional open source system to create Windows installers. It is designed to be as small and flexible as possible and is therefore very suitable for internet distribution.Being a users first experience with your product, a stable and reliable installer is an important component of successful software. With NSIS you can create such installers that are capable of doing everything that is needed to setup your software. More Info »NSIS is script-based and allows you to create the logic to handle even the most complex installation tasks.Portable Version:
http://portableapps.com/apps/development/nsis_portable