There are clients of mine who are content with their VB6 and SQL 2000 applications that I have written them many moons ago. The applications run fine, require some maintenance, some bug fixes from time to time but really run OK for the client. There is no reason in their mind to upgrade (or have my rewrite these in the current versions).
Some of my clients have even had me add on to the code, new features and one has had me develop an entirely new product for them - in VB6. Their request, against my recommendation not to.
My question is, as this may come up again soon, do I start to charge them more for writing software with older technologies? What about maintaining existing software? Access 2000, VB6, SQL Server 2000, even the first versions of Dot-Net as some examples of some of my smallest clients who are perfectly happy and dont wish to pay for new versions written in current technologies.