Steam Wallet Goes Live
"Funds in your Steam Wallet may be used for the purchase of any game on Steam or within a game that supports Steam transactions," Valve wrote on the add funds page of Steam. Users will get the chance to review orders before confirming.
Steam subscribers can add funds in the increments listed below:
UK: £4, £8, £18, £35, £70
US: $5, $10, $25, $50, $100
EU: €5, €10, €25, €50, €100
You'll also need to check out the new subscriber agreement, which states, among other things, that funds added to your wallet are non-refundable and non-transferrable.