I used Allaire's ColdFusion 4.5 when I worked at PayOffshore.Com. I'd never used it prior to that but picked it up very quickly and went on to develop the company's Administration and Billing System using it. This system recorded all customer information and was also used for monthly billing. In effect, it did customer accounting, allowing customers to be billed, view their bill online, then pay online with their credit card. At month end, transaction summaries were exported to the corporate accounting system (Sage).

I developed numerous customer applications using CF4.5 and also lead the development team in creating PayOffshore.Com's Gateway API and Merchant Panel, used by customers to process their client's credit card payments through PayOffshore.Com's systems.

Allaire has since been bought out by Macromedia. ColdFusion has been further developed and integrated with Macromedia's other products.