There is the option of creating a full e-commerce solution. This involves many different components - a merchant account from a bank, a payment gateway service that allows you to accept payments into your merchant account from your website, a shopping cart or payment script that integrates with your payment gateway, and certain elements of the server environment like having an SSL certificate and a static IP. Full e-commerce is much more expensive and time-consuming to develop than PayPal, but it can be integrated into your site for a truly seamless payment experience. It can also save you money in the long run if you are doing a lot of sales.