Re: I lost my Sims 3 disc, is there anything else I can do to download the game without the disc?

If you registered the game on thesims3.com OR bought it on Origin, the serial code can be found in the myGames tab on the Origin client. Download the client from here http://origin.com/download, log in with your data and go to the MyGames tab. Hover over the game and find the i. 

The product code listed there is your serial number (it can be different from your original one if the game was bought before Origin came out)

Read more here: http://answers.ea.com/t5/The-Sims-3/FAQ-Lost-and-broken-DVDs-and-missing-serial-codes-What-to-do/td-p/14230