UltraISO - CD image files are easily created with UltraISO.
PowerISO - PowerISO is a virtual drive that allows users to encode, burn, mount, and even encrypt CDs, DVDs, and BDs. The software can be downloaded from many platforms and sites online.
AnyToISO - AnyToISO converts any format to ISO.
WinCDEmu - WinCDEmu is an open-source CD/DVD/BD emulator.
gBurner - gBurner - A powerful CD, DVD and BD burning software
Virtual CloneDrive - Virtual CloneDrive works and behaves just like a physical CD/DVD/Blu-ray drive, although it only exists virtually.