I have multiple projects in my life but only one notebook.
This means that documents, software, notes, almost everything goes into the same machine and this can be very distractive.
My solution to that is to use Virtual Machines (specifically VMware).
Every time I start a new project I create a virtual machine on my computer so that all the relevant project data and software are there.
The problem is that Virtual Machines are slow, and some times is really annoying to start/stop them. Somehow you pay the price of this separation of concerns with speed.
Does any one has a better solution?