Adding to this, OneNote… very handy to have a page for each project rather than trying to rely on physical sketchbook (e.g. if I need to flip back and find a Pantone code from half a year ago) and images are a lot easier to include than Word.
A coworker showed me Greenshot (freeware) and I have been plugging it after using Snipping Tool for months. http://getgreenshot.org/
Basically just as easy but allows more markup, text, multiple instances running, snipping of a preset area, etc.