For years I've had a paper A4 notebook at work, in which I jot down meeting notes, phone numbers, quick design notes, to do lists, things that have happened etc. This is great, but not very searchable.
Today I installed some software to partially replace the notebook. Not only is it searchable, it is searchable from any PC on the network. It's easy to add notes, and categorise them, and it automatically timestamps each item. Sound familiar? It's a blog.