Think it was Spiny who origionally told us about this software called Freemind. It's an open source mind mapping bit of software which is a complete doddle to use.
Thankfully the guy included a great wee video about how he anally keeps track of his every minute in a mind map, which he can export to excel. Allowing him to bill people as he goes.
I've got a new remit at work and was struggling under the variety of tasks to keep juggling, so put in a wee mind map for current/future work and it's all being handled very easily.
Well so far. I still find it a bit clunky, and the onmouseover way it selects what you're actively targetting is quite annoying.
But well worth a punt for nothing!