My idea is simple:
Customers can buy Gift Vouchers that can be used on the your whmcs panel orders. They would go through an order form and get emailed the voucher and given the voucher code (coupon code) - which can only be used once.
They would be able to print it out or email it to a friend.
£5/£10/£20/£50/£100 vouchers etc..
I have several customers who would like to give a friend a voucher for birthdays etc.. So why not make it automated?
A simple add on might do it - but if enough people want it, then it could be included with the default whmcs installation
Let me know your thoughts on this,
Twilight Web Design CEO