In most of the Asia countries (that I have known of), the common wedding gift will be the money in a red packet. How much to give depends on how good the relationship you are with the married couple. To a closer friend, some will even give their personalized gifts for weddings on top of the red packet. If compare to gift, money is more realistic since the married couple can use it for their own purpose. Sometimes, you think the gift is nice but others will not think the same.