Steam, the popular digital gaming service, has an easy and convenient way to send games as Steam Gift Card 10 USD to your friends, as well as customizing that gift by attaching a personalized message to it.
You can gift a game to send that game directly into their Steam inventory, without the need for sending digital codes. All you need is a Steam account of your own.
You can purchase $5, $10, $25, $50 and $100 digital gift cards on Steam (different currencies depending on the region you are in of course).
You may load the gift card page on the Steam website, or select Store Gift Cards in the Steam client to get started.
Go to a store
Pick up a steam card off the shelf where they have gift cards
Go to the register of the store and pay for the face value of the card
Go to http://www.steampowered.com/wallet and sign in if you aren't already. You will need to create a Steam account if you do not already have one.
Once logged into Steam, please enter your unique Wallet code that you received into the “Steam Wallet Code” field.
Click "Continue" to redeem the credit onto your account. Note: If you have never used Steam Wallet credit on your account, you may be prompted to enter your current address to determine the correct currency.
The value of the Steam Wallet code will be added to your account's Steam Wallet balance. The current available balance will be listed in the upper right hand corner next to [Your username]'s Account.
An email message is sent to the selected friend, and the new gift card is also highlighted in the Steam client.
The following restrictions and rules are in place:
Digital Gift Cards can only be given to friends that have been your friend for at least three days.
The monetary value of the gift card is added to the friend's wallet automatically.
Money is automatically converted to the user's currency when the transfer completes.
Declined gift cards are refunded, either to the original payment method if supported, or otherwise to your Steam wallet.
It is still possible to gift virtual items such as games directly to friends. The new digital gift cards option adds another option to the gifting process.
Alternatively, you can try selling it as long as you have not used it yet. Try a gaming marketplace like https://www.igvault.com/Steam-Items , register and put up your spare key for sale there or Buy Steam Gift Cards