Custom C# code all the way. PHP is cool, too, although with my background I can write pretty much *anything* with C#. I'd love to add Python and Ruby to my belt, as well.
My ultimate goal is to tie all of my disparate tools into a single platform which runs on a VPS. After each agent completes a work task, I'll view an "audit trail" to verify it's been properly executed, then sign-off. Then another agent can pick up where it left off, etc. etc. I want it to be just like an assembly line.
Working hard to get there... I tend to build things in a disciplined OOD/OOP fashion so the transition to one-platform can happen more smoothly.