I'm way behind the times on this, but yesterday was the first time I've played in any kind of depth with Yahoo Pipes. I took a detailed look because I was thinking about how to make a simple stream-processing desktop programming language. Pipes is exactly what I described except for the fact that it only works online. A desktop version would be able to load from Internet or local sources and produce files or effects on the machine. An appropriate module would also allow remote control of the PC, which is a potential security risk, but it's a very interesting idea. Several of the specialised applications I use daily could be replaced with an application like this.
Mokalus of Borg
PS - Time tracking, diary keeping, application scheduling ...
PPS - Possibilities abound.