Optically challenged computers rejoice!
Virtual drive software isn't new, but with the recent surge of ultra portable notebooks that do not have built in optical drives this is a good time to go over one of the free emulation software out there, Slysoft's Virtual CloneDrive.
For those that may not know, a virtual drive emulates a physical drive, in this case an optical drive. This way you can mount a disc image and use it as if a physical disc was inserted into an actual drive.
CloneDrive gives you the ability to mount up to 8 virtual drives at once. Simply right click the virtual drive under My Computer and select the image you would like to mount or just double click the image file itself.
One nice feature of CloneDrive is that it also shows a history of what's been mounted before making it easy to swap out images without the need to browse your computer.
Keep in mind that you will need to convert your CD/DVD to an image format before using CloneDrive. But once you have, loading programs are only a mouse click away.