‘Miss’Organization

Question:

How do you organize your poetry for future retrieval?

By form? (Where did I put that one haiku [read, out of 2,600]?)
By topic? (If so, what topic headings are in your cache?)
By date?
By prompt?

What if I file by form, but want to get together a collection of, say, only love haiku?

Have you found a method that works well for you?