Prepaid cards have seen significant growth in the last couple of years. This has mainly been for gift card applications, and most malls do have a prepaid gift card. Other specialist applications is also available for small target groups. These include incentive payments, wages, etc. These applications will continue to grow. In future most banks will also offer generic prepaid cards.
You can however open a current or savings account, with a cheque card linked. Cheque cards operate in the same way as credit cards, and you can use them for online flight bookings, etc. Your banker may need to motivate approval for a current account, should you have a bad credit rating.
Alternatively Nedbank offers a merchant system called Npay which allows debit cards to be used online. The merchant that you want to buy from must be Npay enabled and the computer you are using must be linked to an Npay terminal, currently at 3@1 stores. You can also use your debit card to book flights at a travel agent, but typically not for car rentals and hotel bookings.