User blog comment:Arbington/ME3 Theories/@comment-1960506-20100803060644

I have found that using impulse or steam, they provide the game to download again even if you have to reformat your computer. Some companies like direct2drive and ea.com make you pay for a backup service to be able to download the game again for a limited time, usually 2 years or so. It depends on where you go to get the game. Impulse and steam are my favorites with impulse being my favorite of the two.