ADRIFT is a relatively new IF development system designed by Campbell Wild that allows you to create your own IF game. It was written in Visual Basic and is programmed for Mirosoft Windows. ADRIFT is intended for people who do not like programming; it sacrifices some power and flexibility for easy usability, but it is still a respected tool with a loyal user base.
While ADRIFT games can be played for free, the generator is shareware and costs $17.
Find out more about ADRIFT at www.adrift.org.uk.