where did I see if i had some unused codes?

go to your "account", select "order and settings", click on "order history", uncheck everything except "unredeemed gifts" --> you should now see a list of your unused codes.

In your purchase history.Right next to every key its listed if its unreedemed,reedemed,gifted(and to who exactly).

EDIT:
Lol. I was a bit too slow :D,but more information is always good.Cheers.

Thanks fellows. It seems I have one little big adventure unredeemed.. any one of you want that?

I didn't know this either, thanks for the info!

Un-used cocks! oh right it was my thread. Damn!