Similar to POV-Ray

Hexagon (software)

HSQLDB

HTML Tidy

HTTrack

Hypertable

Intelligent Input Bus

Internet/Intranet Input Method Framework

IKVM.NET

ImageJ

InfraRecorder

Initng

InnoDB

Interactive Ruby Shell

Ispell

JACK Audio Connection Kit

Jigdo

Kawa (Scheme implementation)

MASSIVE (software)

Autodesk Maya

Mesa (computer graphics)

Metasequoia (software)

GtkRadiant