I'm responsible for maintaining a list of all the applications in my company (about 250). The range is from HR systems that track 80k employees, to manufacturing-type systems responsible for hundreds of millions of dollars of revenue, to web applications with a small user base and not a lot of risk associated to them going down.
The technologies are mostly split between SAP, .Net, and Java, but we have legacy examples of just about everything else you can imagine.
The point of the list is to be able to manage risk and identify opportunities for improvement. For instance, when we find systems that are responsible for core business functionality that are written in clipper, we try to find some money to re-write them. We call the picture of the high-risk apps in the landscape the "heat map".
The list is pretty simple - It really just needs the name, description, ID, DB platform, App platform (ex, SAP, .Net, Java on Weblogic, Mainframe, etc), key interfaces, and key services.
Anyone have any experience building / maintaining a list like this? What should I keep in mind?