Is there any way to install a program once, then run it without a disc?

[acegazda]

The title pretty much states the question, is there such a thing?

 

[Stg-Flame]

Alcohol 120% and Daemon Tools does the trick well enough.

http://www.alcohol-soft.com/

http://www.daemon-tools.cc/dtcc/announcements.php

 

[Schadenfroh]

Alcohol 52% Free Edition, create and mount your own images (Daemon tools does not allow you to make images (only mount), Alcohol 52% Free Edition allows you to do both).